Smart lattice light-sheet microscopy for imaging rare and complex cellular events.

Light-sheet microscopes enable rapid high-resolution imaging of biological specimens; however, biological processes span spatiotemporal scales. Moreover, long-term phenotypes are often instigated by rare or fleeting biological events that are difficult to capture with a single imaging modality. Here, to overcome this limitation, we present smartLLSM, a microscope that incorporates artificial intelligence-based instrument control to autonomously switch between epifluorescent inverted imaging and lattice light-sheet microscopy (LLSM). We apply this approach to two unique processes: cell division and immune synapse formation. In each context, smartLLSM provides population-level statistics across thousands of cells and autonomously captures multicolor three-dimensional datasets or four-dimensional time-lapse movies of rare events at rates that dramatically exceed human capabilities. From this, we quantify the effects of Taxol dose on spindle structure and kinetochore dynamics in dividing cells and of antigen strength on cytotoxic T lymphocyte engagement and lytic granule polarization at the immune synapse. Overall, smartLLSM efficiently detects rare events within heterogeneous cell populations and records these processes with high spatiotemporal four-dimensional imaging over statistically significant replicates.

Phase separation drives aberrant chromatin looping and cancer development.

The development of cancer is intimately associated with genetic abnormalities that target proteins with intrinsically disordered regions (IDRs). In human haematological malignancies, recurrent chromosomal translocation of nucleoporin (NUP98 or NUP214) generates an aberrant chimera that invariably retains the nucleoporin IDR-tandemly dispersed repeats of phenylalanine and glycine residues1,2. However, how unstructured IDRs contribute to oncogenesis remains unclear. Here we show that IDRs contained within NUP98-HOXA9, a homeodomain-containing transcription factor chimera recurrently detected in leukaemias1,2, are essential for establishing liquid-liquid phase separation (LLPS) puncta of chimera and for inducing leukaemic transformation. Notably, LLPS of NUP98-HOXA9 not only promotes chromatin occupancy of chimera transcription factors, but also is required for the formation of a broad 'super-enhancer'-like binding pattern typically seen at leukaemogenic genes, which potentiates transcriptional activation. An artificial HOX chimera, created by replacing the phenylalanine and glycine repeats of NUP98 with an unrelated LLPS-forming IDR of the FUS protein3,4, had similar enhancing effects on the genome-wide binding and target gene activation of the chimera. Deeply sequenced Hi-C revealed that phase-separated NUP98-HOXA9 induces CTCF-independent chromatin loops that are enriched at proto-oncogenes. Together, this report describes a proof-of-principle example in which cancer acquires mutation to establish oncogenic transcription factor condensates via phase separation, which simultaneously enhances their genomic targeting and induces organization of aberrant three-dimensional chromatin structure during tumourous transformation. As LLPS-competent molecules are frequently implicated in diseases1,2,4-7, this mechanism can potentially be generalized to many malignant and pathological settings.

The maize preligule band is subdivided into distinct domains with contrasting cellular properties prior to ligule outgrowth.

The maize ligule is an epidermis-derived structure that arises from the preligule band (PLB) at a boundary between the blade and sheath. A hinge-like auricle also develops immediately distal to the ligule and contributes to blade angle. Here, we characterize the stages of PLB and early ligule development in terms of topography, cell area, division orientation, cell wall rigidity and auxin response dynamics. Differential thickening of epidermal cells and localized periclinal divisions contributed to the formation of a ridge within the PLB, which ultimately produces the ligule fringe. Patterns in cell wall rigidity were consistent with the subdivision of the PLB into two regions along a distinct line positioned at the nascent ridge. The proximal region produces the ligule, while the distal region contributes to one epidermal face of the auricles. Although the auxin transporter PIN1 accumulated in the PLB, observed differential auxin transcriptional response did not underlie the partitioning of the PLB. Our data demonstrate that two zones with contrasting cellular properties, the preligule and preauricle, are specified within the ligular region before ligule outgrowth.

Efficacy of a spatial repellent for control of Aedes-borne virus transmission: A cluster-randomized trial in Iquitos, Peru.

Over half the world's population is at risk for viruses transmitted by Aedes mosquitoes, such as dengue and Zika. The primary vector, Aedes aegypti, thrives in urban environments. Despite decades of effort, cases and geographic range of Aedes-borne viruses (ABVs) continue to expand. Rigorously proven vector control interventions that measure protective efficacy against ABV diseases are limited to Wolbachia in a single trial in Indonesia and do not include any chemical intervention. Spatial repellents, a new option for efficient deployment, are designed to decrease human exposure to ABVs by releasing active ingredients into the air that disrupt mosquito-human contact. A parallel, cluster-randomized controlled trial was conducted in Iquitos, Peru, to quantify the impact of a transfluthrin-based spatial repellent on human ABV infection. From 2,907 households across 26 clusters (13 per arm), 1,578 participants were assessed for seroconversion (primary endpoint) by survival analysis. Incidence of acute disease was calculated among 16,683 participants (secondary endpoint). Adult mosquito collections were conducted to compare Ae. aegypti abundance, blood-fed rate, and parity status through mixed-effect difference-in-difference analyses. The spatial repellent significantly reduced ABV infection by 34.1% (one-sided 95% CI lower limit, 6.9%; one-sided P value = 0.0236, z = 1.98). Aedes aegypti abundance and blood-fed rates were significantly reduced by 28.6 (95% CI 24.1%, ∞); z = -9.11) and 12.4% (95% CI 4.2%, ∞); z = -2.43), respectively. Our trial provides conclusive statistical evidence from an appropriately powered, preplanned cluster-randomized controlled clinical trial of the impact of a chemical intervention, in this case a spatial repellent, to reduce the risk of ABV transmission compared to a placebo.

Excited State Dynamics in Unidirectional Photochemical Molecular Motors.

Unidirectional photochemically driven molecular motors (PMMs) convert the energy of absorbed light into continuous rotational motion. As such they are key components in the design of molecular machines. The prototypical and most widely employed class of PMMs is the overcrowded alkenes, where rotational motion is driven by successive photoisomerization and thermal helix inversion steps. The efficiency of such PMMs depends upon the speed of rotation, determined by the rate of ground state thermal helix inversion, and the quantum yield of photoisomerization, which is dependent on the excited state energy landscape. The former has been optimized by synthetic modification across three generations of overcrowded alkene PMMs. These improvements have often been at the expense of photoisomerization yield, where there remains room for improvement. In this perspective we review the application of ultrafast spectroscopy to characterize the excited state dynamics in PMMs. These measurements lead to a general mechanism for all generations of PMMs, involving subpicosecond decay of a Franck-Condon excited state to populate a dark excited state which decays within picoseconds via conical intersections with the electronic ground state. The model is discussed in the context of excited state dynamics calculations. Studies of PMM photochemical dynamics as a function of solvent suggest exploitation of intramolecular charge transfer and solvent polarity as a route to controlling photoisomerization yield. A test of these ideas for a first generation motor reveals a high degree of solvent control over isomerization yield. These results suggest a pathway to fine control over the performance of future PMMs.

Deep learning enables fast and dense single-molecule localization with high accuracy.

Single-molecule localization microscopy (SMLM) has had remarkable success in imaging cellular structures with nanometer resolution, but standard analysis algorithms require sparse emitters, which limits imaging speed and labeling density. Here, we overcome this major limitation using deep learning. We developed DECODE (deep context dependent), a computational tool that can localize single emitters at high density in three dimensions with highest accuracy for a large range of imaging modalities and conditions. In a public software benchmark competition, it outperformed all other fitters on 12 out of 12 datasets when comparing both detection accuracy and localization error, often by a substantial margin. DECODE allowed us to acquire fast dynamic live-cell SMLM data with reduced light exposure and to image microtubules at ultra-high labeling density. Packaged for simple installation and use, DECODE will enable many laboratories to reduce imaging times and increase localization density in SMLM.

Larger Tumor Size and Elevated Serum Chromogranin A Levels Predict Metastatic Disease on DOTATATE Imaging in Patients with Gastroenteropancreatic Neuroendocrine Tumors.

PURPOSE: DOTATATE PET/CT (DOTATATE) is superior to conventional imaging in detecting metastasis for gastroenteropancreatic neuroendocrine tumors (GEP-NETs). However, limited availability, high-cost, and additive radiation exposure necessitate guidelines for its use. This study seeks to investigate the relationship between clinical characteristics and metastasis on DOTATATE. METHODS: This was a retrospective analysis of 815 patients who underwent DOTATATE at UCLA from 2014 to 2022. After applying inclusion and exclusion criteria, the study cohort consisted of 163 patients with pathologically diagnosed GEP-NETs, who either underwent primary tumor resection within 1-year prior, or had not undergone resection at the time of DOTATATE imaging. The presence of metastasis was determined using DOTATATE. Fisher's exact test, chi-squared test, and Mann-Whitney test were conducted to compare intergroup difference. Multivariate analysis was performed to identify clinical characteristics associated with metastasis on DOTATATE. RESULTS: Of patients with GEP-NETs, 40.5% (n = 66) were diagnosed with metastases by using DOTATATE. Those with metastatic disease were more likely to exhibit a larger primary tumor size (median 3.4 vs. 1.2, cm, P < 0.001), elevated serum chromogranin A level (CgA, median 208 vs. 97, mg/ml, P = 0.005), and higher tumor grade (P < 0.001). Primary tumor size ≥2 cm and serum CgA level ≥150 ng/mL for metastatic disease had a sensitivity and specificity of 64% and 89%, and 72% and 59%, respectively. Multivariate analysis demonstrated that primary tumor size (≥2/<2, cm, odds ratio [OR] 47.90, P < 0.001), tumor functionality (functional/nonfunctional, adjusted OR 10.17 P = 0.008), serum CgA level (≥150/<150, ng/ml, OR 6.25, P = 0.005), and tumor grade G2 (G2/G1, OR 9.6, P < 0.001) were independently associated with metastases on DOTATATE. CONCLUSIONS: Among patients with GEP-NETs, primary tumor size ≥2 cm, serum CgA level ≥150 ng/mL, and tumor grade G2 are associated with an increased risk of metastases on DOTATATE, and these predictors may be helpful to identify patients where DOTATATE is indicated for complete staging.

A Call for More Culture-Based Research to Understand Body Dissatisfaction and Disordered Eating in Men: Commentary on Monocello et al. (2024).

Using culture-based approaches, Monocello et al. revealed that young Korean men generally shared the same perceptions of fatness, including three categories ("too thin," "balanced," and "too fat"). The "balanced" category was most consistent with local South Korean culture, and the "too fat" category was associated with higher body dissatisfaction and disordered eating. Even though cultural differences in body ideals are an essential factor to consider in the development of body dissatisfaction and disordered eating, little research has applied culture-based approaches to explore body ideals in men, including how these ideals may be related to men's body image or eating behaviors. Thus, Monocello et al.'s work is a timely and vital contribution to the literature. In this commentary, we expand on Monocello et al.'s work by not only illustrating the roles of local cultures but also introducing the potential influences of external cultures via acculturation in shaping body ideals which, in turn, contribute to body dissatisfaction and disordered eating in men. We also provide future research directions to call for more culture-based research to understand body dissatisfaction and disordered eating among men in different cultural contexts.

Beyond Age, BMI, Gender Identity, and Gender Minority Stress, Weight Bias Internalization Is Uniquely Associated With More Eating and Body Image Disturbances and Poor Physical and Mental Health in Chinese Gender-Diverse Adults.

OBJECTIVE: Weight bias internalization (WBI) is a robust, positive correlate of negative health outcomes; however, this evidence base primarily reflects cisgender individuals from Western cultural contexts. Gender-diverse individuals from non-Western cultural contexts (e.g., China) are at potentially high risk for WBI. Yet, no research has examined WBI and associated negative health consequences in this historically underrepresented population. METHOD: A cross-sectional, online survey sampled Chinese gender-diverse individuals (N = 410, Mage = 22.33 years). Variables were self-reported, including demographics, WBI, body shame, body dissatisfaction, disordered eating, physical and mental health status, and gender minority stress (e.g., internalized cisgenderism). Analyses included correlations and multiple hierarchical regressions. RESULTS: Pearson bivariate correlations demonstrated associations between higher WBI and more eating and body image disturbances and poor physical and mental health. After adjusting for age, BMI, gender identity, and gender minority stress, higher WBI was uniquely and positively associated with higher body shame, higher body dissatisfaction, higher disordered eating, and poor physical and mental health. Notably, WBI accounted for more unique variance in eating and body image disturbances (13%-25% explained by WBI) than physical and mental health (1%-4% explained by WBI). DISCUSSION: While replication with longitudinal and experimental designs is needed to speak to the temporal dynamics and causality, our findings identify WBI as a unique, meaningful correlate of eating and body image disturbances in Chinese gender-diverse adults.

Differences in Thinness- and Muscularity-Oriented Eating and Body Image Disturbances and Psychosocial Well-Being in Chinese Sexual Minority Men Reporting Top, Bottom, and Versatile Sexual Self-Labels.

In addition to describing sexual partner preferences, sexual self-labels in gay and bisexual (henceforth, sexual minority) men, such as top, bottom, and versatile, are associated with psychological characteristics (e.g., gendered personality traits). No research has explored the association between sexual self-labels and eating and body image disturbances in sexual minority men. Research in sexual minority men from China is particularly valuable and needed due to recent rises in rates of eating and body image disturbances and unique, minority-specific stressors experienced by Chinese sexual minority populations. We adopted an online, cross-sectional study in a sample of sexual minority men from China (N = 403; tops, n = 256, bottoms, n = 95, versatiles, n = 52). Bottoms reported higher thinness internalization, lower muscularity internalization, higher body fat dissatisfaction, and higher psychological distress than tops. Bottoms' weight bias internalization was higher than tops' and versatiles' reports and, compared to versatiles, bottoms also reported higher psychosocial impairment related to eating disorder psychopathology. Compared to versatiles, tops reported higher drive for muscularity and muscularity-oriented disordered eating. Adjusting for age, psychological distress, and psychosocial impairment, tops reported higher muscularity internalization than bottoms and higher drive for muscularity and muscularity-oriented disordered eating than both bottoms and versatiles. Findings suggested unique relations between sexual self-labels and eating and body image disturbances in Chinese sexual minority men. Replication and validation of the temporal order between sexual self-labels and eating and body image disturbances is needed, including assessment of social factors (e.g., femmephobia, minority stress) that may help explain the links between sexual self-labels and eating pathology.

Substituent effects on first generation photochemical molecular motors probed by femtosecond stimulated Raman.

Unidirectional photochemical molecular motors can act as a power source for molecular machines. The motors operate by successive excited state isomerization and ground state helix inversion reactions, attaining unidirectionality from an interplay of steric strain and stereochemistry. Optimizing the yield of the excited state isomerization reaction is an important goal that requires detailed knowledge of excited state dynamics. Here, we investigate the effect of electron withdrawing and donating substituents on excited state structure and ultrafast dynamics in a series of newly synthesized first generation photochemical molecular motors. All substituents red-shift the absorption spectra, while some modify the Stokes shift and render the fluorescence quantum yield solvent polarity dependent. Raman spectra and density functional theory calculations reveal that the stretching mode of the C=C "axle" in the electronic ground state shows a small red-shift when conjugated with electron withdrawing substituents. Ultrafast fluorescence measurements reveal substituent and solvent polarity effects, with the excited state decay being accelerated by both polar solvent environment and electron withdrawing substituents. Excited state structural dynamics are investigated by fluorescence coherence spectroscopy and femtosecond stimulated Raman spectroscopy. The time resolved Raman measurements are shown to provide structural data specifically on the Franck-Condon excited state. The C=C localized modes have a different substituent dependence compared to the ground state, with the unsubstituted motor having the most red-shifted mode. Such measurements provide valuable new insights into pathways to optimize photochemical molecular motor performance, especially if they can be coupled with high-quality quantum molecular dynamics calculations.

The relation between questionnaire-measured self-reported emotional eating and disordered eating behaviors: A meta-analysis of nearly three decades of research.

Extensive research exists on the association between self-reported emotional eating (EE) and disordered eating (DE) behaviors. Heterogeneity exists by type (e.g., unidimensional vs. multidimensional) and valence (e.g., negative vs. positive) of self-reported EE, and no previous meta-analyses have examined the association between self-reported EE and DE behaviors. A total of 67 studies (N = 26,289; 43 reporting relations in one model, and 24 reporting relations in more than one model) met inclusion criteria; ranges for age and publication date were 18.0-61.8 years old and 1995 to 2022. Five models quantified relations between DE behaviors and 1) broad negative EE, 2) EE in response to depression, 3) EE in response to anger and anxiety, 4) EE in response to boredom, and 5) EE in response to positive emotions. Using random-effects models, pooled Cohen's d effect sizes suggested small, positive relations between DE behaviors and self-reported broad negative EE (d = 0.40, p < 0.001), EE-depression (d = 0.41, p < 0.001), EE-anger/anxiety (d = 0.35, p < 0.001), and EE-boredom (d = 0.38, p < 0.001). A significant, but very small, positive relation was observed between DE behaviors and self-reported EE-positive (d = 0.08, p = 0.01). Subgroup analyses suggested a medium, positive relation between self-reported broad negative EE and binge eating (d = 0.53, p < 0.001) and a small, positive relation between self-reported broad negative EE and dietary restraint (d = 0.20, p < 0.001). Significant heterogeneity was identified across all models except for the EE-boredom and DE behaviors model. Higher BMI, but not age, clinical status, or type of DE behavior strengthened the positive relation between self-reported broad negative EE and DE behaviors. Findings support previous research suggesting that negative and positive EE are distinct constructs, with negatively valenced EE being more closely associated with DE behaviors, especially binge eating.

Single-cell sequencing reveals suppressive transcriptional programs regulated by MIS/AMH in neonatal ovaries.

Müllerian inhibiting substance (MIS/AMH), produced by granulosa cells of growing follicles, is an important regulator of folliculogenesis and follicle development. Treatment with exogenous MIS in mice suppresses follicle development and prevents ovulation. To investigate the mechanisms by which MIS inhibits follicle development, we performed single-cell RNA sequencing of whole neonatal ovaries treated with MIS at birth and analyzed at postnatal day 6, coinciding with the first wave of follicle growth. We identified distinct transcriptional signatures associated with MIS responses in the ovarian cell types. MIS treatment inhibited proliferation in granulosa, surface epithelial, and stromal cell types of the ovary and elicited a unique signature of quiescence in granulosa cells. In addition to decreasing the number of growing preantral follicles, we found that MIS treatment uncoupled the maturation of germ cells and granulosa cells. In conclusion, MIS suppressed neonatal follicle development by inhibiting proliferation, imposing a quiescent cell state, and preventing granulosa cell differentiation.

Early targeted heart rate exercise is safe and May hasten return-to-duty in service members with acute concussion, a preliminary study.

OBJECTIVE: To evaluate the feasibility of an exercise tolerance assessment and intervention added to the Progressive Return to Activity Clinical Recommendations (PRA-CR) in acutely concussed service members (SMs). METHODS: This non-randomized, pilot trial was performed at one center. SMs in the experimental group (ERG) performed the Buffalo Concussion March-in-place Test (BCMT) at every clinic visit and were prescribed at least 20 minutes/day of targeted exercise in addition to PRA-CR. Data for the control group (SCG) were extracted from the same clinic immediately prior to ERG. SMs in both groups were assessed by the same clinician to determine return-to-duty. RESULTS: BCMT identified concussion-related exercise intolerance in 100% (n = 14) at screening visit (mean 3.4 days after injury) and in 0% (n = 7) who had recovered. No adverse effects were associated with BCMT. The estimated recovery time for ERG who performed the exercise intervention (n = 12) was 17.0 (12.8, 21.2) days and for SCG (n = 15) was 23.7 (19.9, 27.5) days (p = 0.039). CONCLUSION: Assessment of exercise tolerance was feasible and could be incorporated into the PRA-CR. Future definitive, randomized controlled trials should be performed to assess the effectiveness of exercise reset program for SMs after concussion.

Exploring the moderating roles of dispositional mindfulness and body image flexibility in the association between body dissatisfaction and disordered eating in Chinese adolescents.

OBJECTIVES: Previous research suggests potential moderating roles of dispositional mindfulness and body image flexibility in the association between body dissatisfaction and disordered eating. However, relevant research is mainly conducted on adult women from Western countries, and limited evidence exists for adolescent samples, especially from non-Western contexts (e.g., China). Thus, this study aimed to examine the moderating roles of dispositional mindfulness and body image flexibility in the relationship between body dissatisfaction and disordered eating in Chinese adolescents. METHOD: We recruited 545 Chinese adolescents (53.9% boys, aged 12-16 years) who completed measures of body dissatisfaction, dispositional mindfulness, body image flexibility, and disordered eating. Moderation analyses were examined with PROCESS macro on SPSS. RESULTS: In separate models, both higher dispositional mindfulness and body image flexibility weakened relationships between body dissatisfaction and disordered eating. However, when both dispositional mindfulness and body image flexibility were entered into the same moderation model, only body image flexibility showed a significant moderating effect. DISCUSSION: Both dispositional mindfulness and body image flexibility may weaken the association between body dissatisfaction and disordered eating in adolescents. However, body image flexibility might have a stronger effect than dispositional mindfulness. These findings suggest that interventions aimed at reducing body dissatisfaction to prevent disordered eating in adolescents may pay more attention to adolescents' body image flexibility.

Psychometric network analysis of the Intuitive Eating Scale-2 in Chinese general adults.

The Intuitive Eating Scale-2 (IES-2) is a measure of intuitive eating behaviors that has been extensively validated, with traditional latent variable modeling approaches, in youth and adults from many different populations, including college students in China. However, there is still a lack of research on the psychometric properties of the IES-2 in adults from the Chinese general population. Moreover, psychometric network analysis, as a complement to traditional latent variable modeling approaches, has not been used for examining the psychometric properties of the IES-2. Thus, the present study used a psychometric network approach to evaluate the psychometric properties of the IES-2 in Chinese adults from the general population. A sample of 700 Chinese general adults (50% women; Mage = 31.13 years, SD = 9.19) recruited online were included in the present study. Psychometric network analysis was performed. Exploratory graph analysis (EGA) identified four dimensions, which were well separated in the estimated network. The network structure showed excellent stability and metric measurement invariance (i.e., network loadings) across men and women. Furthermore, several items on the IES-2 were identified as key nodes in the network of the IES-2 that may be important for the development and maintenance of intuitive eating. For example, two items (i.e., "I trust my body to tell me when to eat," and "I trust my body to tell me when to stop eating") related to reliance on body cues were the most impactful nodes in the complete network. The findings of our study provide a greater understanding of the IES-2 from the perspective of network analysis and have implications for applications of intuitive eating interventions for general populations.

Control of Photoconversion Yield in Unidirectional Photomolecular Motors by Push-Pull Substituents.

Molecular motors based on the overcrowded alkene motif convert light energy into unidirectional mechanical motion through an excited state isomerization reaction. The realization of experimental control over conversion efficiency in these molecular motors is an important goal. Here, we combine the synthesis of a novel "push-pull" overcrowded alkene motor with photophysical characterization by steady state and ultrafast time-resolved electronic spectroscopy. We show that tuning of the charge transfer character in the excited state has a dramatic effect on the photoisomerization yield, enhancing it to near unity in nonpolar solvents while largely suppressing it in polar solvents. This behavior is explained through reference to solvent- and substituent-dependent potential energy surfaces and their effect on conical intersections to the ground state. These observations offer new routes to the fine control of motor efficiency and introduce additional degrees of freedom in the synthesis and exploitation of light-driven molecular motors.

3D ATAC-PALM: super-resolution imaging of the accessible genome.

To image the accessible genome at nanometer scale in situ, we developed three-dimensional assay for transposase-accessible chromatin-photoactivated localization microscopy (3D ATAC-PALM) that integrates an assay for transposase-accessible chromatin with visualization, PALM super-resolution imaging and lattice light-sheet microscopy. Multiplexed with oligopaint DNA-fluorescence in situ hybridization (FISH), RNA-FISH and protein fluorescence, 3D ATAC-PALM connected microscopy and genomic data, revealing spatially segregated accessible chromatin domains (ACDs) that enclose active chromatin and transcribed genes. Using these methods to analyze genetically perturbed cells, we demonstrated that genome architectural protein CTCF prevents excessive clustering of accessible chromatin and decompacts ACDs. These results highlight 3D ATAC-PALM as a useful tool to probe the structure and organizing mechanism of the genome.

Selective Analysis of Redox Processes at the Electrode Interface with Time-Resolved Raman Spectroscopy.

Electrochemistry and electrochemical reactions are increasingly important in the transition to a sustainable chemical industry. The electron transfer that drives such reactions takes place within nanometers of the electrode surface, and follow-up chemical reactions take place within the diffusion layer. Hence, understanding electrochemical reactions requires time-, potential-, and spatially resolved analysis. The confocal nature of Raman spectroscopy provides high spatial resolution, in addition to detailed information on molecular structure. The intrinsic weakness of nonresonant Raman scattering, however, is not sensitive enough for relatively minor changes to the solution resulting from reactions at the electrode interface. Indeed, the limit of detection is typically well above the concentrations used in electrochemical studies. Here, we show that surface-enhanced Raman scattering (SERS) and resonance Raman (rR) spectroscopy allow for spatially and time-resolved analysis of solution composition at (<1-2 nm) and near (within 5 µm) the electrode surface, respectively, in a selective manner for species present at low (<1 mM) concentrations. We show changes in concentration of species at the electrode surface, without the need for labels, specific adsorption, or resonance enhancement, using a SERS-active gold electrode prepared readily by electrochemical surface roughening. A combination of smooth and roughened gold electrodes is used to distinguish between surface and resonance enhancement using the well-known redox couples ferrocene and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). We discuss the impact of specific adsorption on the spectral analysis with the ruthenium(II) polypyridyl complex, [Ru(bpy)3]2+. The dual function of the electrode (surface enhancement and electron transfer) in the analysis of solution processes is demonstrated with the reversible oxidation of TMA (4,N,N-trimethylaniline), where transient soluble species are identified in real time, with rapid spectral acquisition, making use of localized enhancement. We anticipate that this approach will find use in elucidating electro(catalytic) reactions at electrode interfaces.

RETRACTED - Intra-individual Cognitive Variability: An Examination of ANAM4 TBI-MIL Simple Reaction Time Data from Service Members with and without Mild Traumatic Brain Injury.

Objectives: The Automated Neuropsychological Assessment Metrics 4 TBI-MIL (ANAM4) is a computerized cognitive test often used in post-concussion assessments with U.S. service members (SMs). Existing evidence, however, remains mixed regarding ANAM4's ability to identify cognitive issues following mild traumatic brain injury (mTBI). Studies typically examine ANAM4 by comparing mean scores to baseline or normative scores. A more fine-grained approach involves examining inconsistency within an individual's performance. Methods: Data from a sample of 231 were healthy control SMs and 100 SMs within 7 days of mTBI who took the ANAM4 were included in analyses. We examine each individual's performance on a simple reaction time (SRT) subtest that is administered at the beginning (SRT1) and end (SRT2) of the ANAM4 battery, and calculate the standard deviation of difference scores by trial across administrations. Results: Multivariate analysis of variance and univariate analyses revealed group differences across all comparisons (p<.001) with pairwise comparisons revealing higher intra-individual variability and slower raw reaction time for the mTBI group compared with controls. Effect sizes were small though exceeded the recommended minimum practical effect size (ES>0.41). Conclusions: While inconsistencies in performance are often viewed as noise or test error, the results suggest intra-individual cognitive variability may be more sensitive than central tendency measures (i.e., comparison of means) in detecting changes in cognitive function in mTBI. Additionally, the findings highlight the utility of ANAM4's repeating a subtest at two points in a battery to explore within-subject differences in performance. (JINS, 2017, 23, 1-6).