Boat noise impedes vocalizations of wild plainfin midshipman fish.

Marine noise is recognised as a growing threat that can induce maladaptive behavioural changes in many aquatic animals, including fishes. The plainfin midshipman is a soniferous fish with a prolonged breeding period, during which males produce tonal hums that attract females, and grunts and growls during agonistic interactions. In this study, we used acoustic recordings to assess the effects of boat noise on the presence, peak frequencies, and durations of plainfin midshipman calls in the wild. We found that all three call types were less likely to occur, and the peak frequencies of hums and grunts increased in the presence of boat noise. We also show that loud and quiet boat noise affected plainfin midshipman vocalizations similarly. As anthropogenic noise is likely to increase in the ocean, it will be important to understand how such noise can affect communication systems, and consequently population health and resiliency.

Lay Health Worker Interventions in Rheumatology: A Scoping Review.

OBJECTIVE: To determine next steps for lay health worker (LHW) intervention research, specifically in patients with rheumatic musculoskeletal diseases (RMDs), there is a need to establish what strategies have been effective for chronic disease management thus far. The goal of this scoping review is to collate the literature of LHW interventions for adults with RMDs to inform next steps for LHW research. METHODS: A comprehensive literature search was performed in the following databases from inception to September 2021: Ovid Medline, Ovid Embase, CINAHL, PsycINFO, and The Cochrane Library. Studies retrieved were then screened for eligibility against predefined inclusion and exclusion criteria. RESULTS: Twenty-two articles were eligible and included in this review. The most common RMDs studied, not mutually exclusive, were osteoarthritis (n = 13), rheumatoid arthritis (n = 9), and unspecified or other RMD (n = 14). Most studies had a homogenous patient population, enrolling White, non-Hispanic, or Latina women over the age of 60 (n = 13). Eight studies observed statistically significant results in the intervention arm compared with the control. Only one of these studies exhibited sustained treatment effects past one year. CONCLUSION: There are not enough data to conclude if LHW interventions have a positive, null, or negative effect on patients with RMDs. Future LHW interventions should specify a priori hypotheses, be powered to detect statistical significance for primary outcomes, employ a theoretical framework, include an active control, describe training protocols for LHWs, and increase minority representation to establish the effectiveness of LHWs for patients with RMDs.

Short-Term Dorsal Genital Nerve Stimulation Increases Subjective Arousal in Women With and Without Spinal Cord Injury: A Preliminary Investigation.

OBJECTIVES: Female sexual dysfunction (FSD) affects an estimated 40% of women. Unfortunately, FSD is understudied, leading to limited treatment options for FSD. Neuromodulation has shown some success in alleviating FSD symptoms. We developed a pilot study to investigate the short-term effect of electrical stimulation of the dorsal genital nerve and tibial nerve on sexual arousal in healthy women, women with FSD, and women with spinal cord injury (SCI) and FSD. MATERIALS AND METHODS: This study comprises a randomized crossover design in three groups: women with SCI, women with non-neurogenic FSD, and women without FSD or SCI. The primary outcome measure was change in vaginal pulse amplitude (VPA) from baseline. Secondary outcome measures were changes in subjective arousal, heart rate, and mean arterial pressure from baseline. Participants attended one or two study sessions where they received either transcutaneous dorsal genital nerve stimulation (DGNS) or tibial nerve stimulation (TNS). At each session, a vaginal photoplethysmography sensor was used to measure VPA. Participants also rated their level of subjective arousal and were asked to report any pelvic sensations. RESULTS: We found that subjective arousal increased significantly from before to after stimulation in DGNS study sessions across all women. TNS had no effect on subjective arousal. There were significant differences in VPA between baseline and stimulation, baseline and recovery, and stimulation and recovery periods among participants, but there were no trends across groups or stimulation type. Two participants with complete SCIs experienced genital sensations. CONCLUSIONS: To our knowledge, this is the first study to measure sexual arousal in response to short-term neuromodulation in women. This study indicates that short-term DGNS but not TNS can increase subjective arousal, but the effect of stimulation on genital arousal is inconclusive. This study provides further support for DGNS as a treatment for FSD.

Examining the Relationship Between Value and Patient Satisfaction With Treatment in Total Joint Arthroplasty.

Background: A shift toward performance, cost, outcomes, and patient satisfaction has occurred with healthcare reform promoting value-based programs. The purpose of this study was to evaluate the relationship between patient satisfaction and value with treatment in a cohort of patients undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA). Methods: Value was determined by the relationship of treatment outcome with episodic cost. Measurements included both clinical outcomes and patient-reported outcomes. Participating surgeons took part in the modified Delphi method resulting in an algorithm measuring patient value. Treatment outcome, cost, and resultant value (outcome/cost) of both TKA and THA were evaluated using binomial logistic regression by adjusting for age, gender, body mass index, Charlson comorbidity index, tobacco, education, and income with patient-reported satisfaction as the outcome. Results: This study had a total of 909 patients (TKA n = 438; THA n = 471), with an average age of 67 (TKA) and 65 (THA) years. Patient satisfaction shared a significant positive relationship with treatment outcome for TKA (odds ratio [OR] = 1.53, confidence interval [CI] = 1.35-1.73, P < .001) and THA (OR = 1.93, CI = 1.62-2.29, P < .001). Higher value was associated with a significantly higher odds of patient satisfaction for both TKA (OR = 1.39, CI = 1.25-1.54, P < .001) and THA (OR = 1.70, CI = 1.47-1.97, P < .001). Conclusions: This study showed a positive relationship between treatment outcome but not cost with subsequent value and patient satisfaction. This method provides a promising approach to comprehensively evaluate outcomes, cost, and value of total joint arthroplasty procedures. This approach can help predict the probability of value-driven patient satisfaction.

Phase Behavior and Rheological Properties of Size-Fractionated MXene (Ti3C2Tx) Dispersions.

Understanding the dispersion behavior of MXenes is interesting from a fundamental colloid science perspective and critical to enabling the fluid-phase manufacturing of MXene devices with controlled microstructures and properties. However, the polydispersity, irregular shape, and charged surfaces of MXenes result in a complex phase behavior that is difficult to predict through theoretical calculations. As two-dimensional (2D) nanomaterials, MXenes can form lyotropic liquid crystal phases, gels, and aggregates. This work aims to elucidate the effects of MXene (Ti3C2Tx) sheet size on their phase behavior and associated rheological properties. Aqueous dispersions of large sheets with an average lateral dimension of 3.0 µm, small sheets with an average lateral dimension of 0.3 µm, and a bimodal mixture of the two sizes were investigated by using cross-polarized optical microscopy and rheology. At low concentrations, the large MXene dispersions exhibited lyotropic liquid crystal behavior and extended aligned textures, but increasing concentration resulted in the formation of dense flocs. Dispersions of small sheets formed small birefringent domains with increasing concentration but lacked long-range ordering. A bimodal mixture of these sizes enabled the formation of liquid crystalline phases with extended aligned textures with less floc formation. These results provide insights into using polydispersity to tune dispersion microstructure and rheological properties that can be applied to designing dispersions for fluid-phase manufacturing methods, such as direct ink writing.

Primary and Secondary Organic Aerosol Formation from Asphalt Pavements.

Asphalt is ubiquitous across cities and a source of organic compounds spanning a wide range of volatility and may be an overlooked source of urban organic aerosols. The emission rate and composition depend strongly on temperature, but emissions have been observed at both application temperatures and surface temperatures during warm sunny days. Here we report primary organic aerosol (POA) emissions and secondary organic aerosol (SOA) production from asphalt. We reheated real-world asphalt samples to application-relevant temperatures (∼130 °C) and typical summertime road-surface temperatures (∼55 °C) and then flushed the emitted vapors into an environmental oxidation chamber containing ammonium sulfate seed particles. SOA was then formed following the photo-oxidation of emissions under high-NOx conditions typical of urban atmospheres. We find that POA only forms at application temperature as it does not require further oxidation, whereas SOA forms under both conditions; with the resulting POA and SOA both being semi-volatile. While total OA formation rates were substantially greater under the limited time spent under application conditions, SOA formation from passive asphalt heating presents a potential long-term source, as heating continues for the lifetime of the road surface. This suggests that persistent asphalt solar heating is likely a considerable and continued source of summertime SOA in urban environments.

Return to Sport Using Corticosteroid Injections for Knee Pain in Triathletes.

Introduction Despite the prevalence of corticosteroid injections in athletes, little is known about their efficacy in triathletes. We aim to assess attitudes, use, subjective effectiveness, and time to return to sport with corticosteroid injections compared to alternative methods in triathletes with knee pain. Methods This is an observational study during the COVID-19 pandemic. Triathletes answered a 13-question survey posted to three triathlon-specific websites. Results Sixty-one triathletes responded, 97% of whom experienced knee pain at some point in their triathlete career; 63% with knee pain received a corticosteroid injection as treatment (average age 51 years old). The most popular attitude (44.3%) regarding corticosteroid injections was "tried them, with good improvement". Most found the cortisone injection helpful for two to three months (28.6%), or more than one year (28.6%); of individuals who found the injections useful for more than one year, four-eight (50%) had received multiple injections during that same period. After injection, 80.6% returned to sport within one month. The average age of people using alternative treatment methods was 39 years old; most returned to sport within one month (73.7%). Compared to alternative methods, there was an ~80% higher odds of returning to sport within one month using corticosteroid injections; however, this relationship was not significant (OR=1.786, p=0.480, 95% CI:0.448-7.09). Conclusion This is the first study to examine corticosteroid use in triathletes. Corticosteroid use is more common in older triathletes and results in subjective pain improvement. A strong association does not exist for a quicker return to sport using corticosteroid injections compared to alternative methods. Triathletes should be counseled on the timing of injections, duration of side effects, and be aware of potential risks.

Acute dorsal genital nerve stimulation increases subjective arousal in women with and without spinal cord injury: a preliminary investigation.

Introduction: Female sexual dysfunction (FSD) impacts an estimated 40% of women. Unfortunately, female sexual function is understudied, leading to limited treatment options for FSD. Neuromodulation has demonstrated some success in improving FSD symptoms. We developed a pilot study to investigate the short-term effect of electrical stimulation of the dorsal genital nerve and tibial nerve on sexual arousal in healthy women, women with FSD, and women with spinal cord injury (SCI) and FSD. Methods: This study consists of a randomized crossover design in three groups: women with SCI, women with non-neurogenic FSD, and women without FSD or SCI. The primary outcome measure was change in vaginal pulse amplitude (VPA) from baseline. Secondary outcome measures were changes in subjective arousal, heart rate, and mean arterial pressure from baseline. Participants attended one or two study sessions where they received either transcutaneous dorsal genital nerve stimulation (DGNS) or tibial nerve stimulation (TNS). At each session, a vaginal photoplethysmography sensor was used to measure VPA. Participants also rated their level of subjective arousal and were asked to report any pelvic sensations. Results: We found that subjective arousal increased significantly from before to after stimulation in DGNS study sessions across all women. TNS had no effect on subjective arousal. There were significant differences in VPA between baseline and stimulation, baseline and recovery, and stimulation and recovery periods among participants, but there were no trends across groups or stimulation type. Two participants with complete SCIs experienced genital sensations. Discussion: This is the first study to measure sexual arousal in response to acute neuromodulation in women. This study demonstrates that acute DGNS, but not TNS, can increase subjective arousal, but the effect of stimulation on genital arousal is inconclusive. This study provides further support for DGNS as a treatment for female sexual dysfunction.

Attitudes toward Help-Seeking for Sexual Problems among College Women.

Prior research has indicated that 65-70% of college age women have experienced at least one sexual problem. Sexual problems are associated with higher rates of depression, anxiety, and relationship distress; however, few college age women seek professional help for sexual difficulties. The present study used the Theory of Planned Behavior to explore how adherence to traditional feminine norms and self-stigma are associated with intention to seek professional psychological help for a sexual difficulty. Results of structural equation modeling analysis demonstrated approximate fit in a sample of 259 college women. The structural model indicated that self-stigma and stronger endorsement of specific feminine gender norms (i.e., romantic relationship, sexual fidelity, sweet and nice) were found to be associated with less intention to seek help for a sexual problem. We discuss future research directions and implications for clinical services.

Complications Following Ulnar Artery Catheterization for Coronary Angiography.

BACKGROUND: Use of radial and ulnar access has increased due to its perceived benefits over femoral access. Ulnar artery catheterization can place patients at risk of significant complications, including pseudoaneurysm, expanding hematoma, compartment syndrome, ulnar nerve injury, and critical hand ischemia. The purpose of this study was to describe complications specific to ulnar artery catheterization. METHODS: After obtaining institutional review board approval, a retrospective review was performed on all patients who underwent ulnar artery catheterization at our institution between 2019 and 2021. Complications were assessed, and complication rates were compared with previously published studies on ulnar artery catheterization for coronary angiography (percutaneous coronary intervention). RESULTS: A total of 41 patients were available for review with a mean age of 59 years. Of these, 17 patients (41%) sustained complications in the immediate postprocedural period. These complications included hematoma (12 patients, 29%), pseudoaneurysm (1 patient, 2%), ulnar artery thrombosis (1 patient, 2%), ulnar neuropathy (3 patients, 7%), arterial damage requiring repair (2 patients, 5%), transient ischemia (3 patients, 7%), and compartment syndrome (2 patients, 5%). Three of these patients (7%) required operative intervention, and several were admitted to the hospital for an additional period of observation. CONCLUSIONS: This series highlights the significant risks associated with ulnar artery catheterization for percutaneous procedures. Complications include pseudoaneurysm, expanding hematoma, compartment syndrome, ulnar nerve damage, and critical hand ischemia. Several of these patients required urgent or emergent surgical intervention, with some patients experiencing ongoing ulnar nerve symptoms.

Fluorescence in situ hybridisation in Carnoy's fixed tonsil tissue.

Fluorescence in situ hybridisation (FISH) is a powerful molecular technique that enables direct visualisation of specific bacterial species. Few studies have established FISH protocols for tonsil tissue in Carnoy's fixative, accordingly limiting its application to investigate the pathogenesis of tonsillar hyperplasia. Tonsil tissue from 24 children undergoing tonsillectomy for either recurrent tonsillitis or sleep-disordered breathing were obtained during a previous study. The specificity of each of the five FISH probes (Fusobacterium spp., Bacteroides spp., Streptococcus spp., Haemophilus influenzae and Pseudomonas spp.) were successfully optimised using pure and mixed bacterial isolates, and in Carnoy's fixed tonsil tissue. Bacteroides spp. were present in 100% of patients with microcolonies. In comparison, the prevalence of Fusobacterium spp. was 93.8%, Streptococcus spp. 85.7%, H. influenzae 82.35% and Pseudomonas spp. 76.5%. Notable differences in the organisation of bacterial taxa within a single microcolony were also observed. This is the first study to establish a robust FISH protocol identifying multiple aerobic and anaerobic bacteria in Carnoy's fixed tonsil tissue. This protocol provides a strong foundation for combining histological and microbiological analyses of Carnoy's fixed tonsil samples. It may also have important implications on the analysis of microorganisms in other human tissues prepared using the same techniques.

Limited Secondary Organic Aerosol Production from Acyclic Oxygenated Volatile Chemical Products.

Volatile chemical products (VCPs) have recently been identified as potentially important unconventional sources of secondary organic aerosol (SOA), in part due to the mitigation of conventional emissions such as vehicle exhaust. Here, we report measurements of SOA production in an oxidation flow reactor from a series of common VCPs containing oxygenated functional groups and at least one oxygen within the molecular backbone. These include two oxygenated aromatic species (phenoxyethanol and 1-phenoxy-2-propanol), two esters (butyl butyrate and butyl acetate), and four glycol ethers (carbitol, methyl carbitol, butyl carbitol, and hexyl carbitol). We measured gas- and particle-phase products with a suite of mass spectrometers and particle-sizing instruments. Only the aromatic VCPs produce SOA with substantial yields. For the acyclic VCPs, ether and ester functionality promotes fragmentation and hinders autoxidation, whereas aromatic rings drive SOA formation in spite of the presence of ether groups. Therefore, our results suggest that a potential strategy to reduce urban SOA from VCPs would be to reformulate consumer products to include less oxygenated aromatic compounds.

Supraspinatus muscle architecture and physiology in a rabbit model of tenotomy and repair.

Chronic rotator cuff tears can cause severe functional deficits. Addressing the chronic fatty and fibrotic muscle changes is of high clinical interest; however, the architectural and physiological consequences of chronic tear and repair are poorly characterized. We present a detailed architectural and physiological analysis of chronic tear and repair (both over 8 and 16 wk) compared with age-matched control rabbit supraspinatus (SSP) muscles. Using female New Zealand White Rabbits (n = 30, n = 6/group) under 2% isoflurane anesthesia, the SSP was surgically isolated and maximum isometric force was measured at four to six muscle lengths. Architectural analysis was performed, and maximum isometric stress was computed. Whole muscle length-tension curves were generated using architectural measurements to compare experimental physiology to theoretical predictions. Architectural measures are consistent with persistent radial and longitudinal atrophy over time in tenotomy that fails to recover after repair. Maximum isometric force was significantly decreased after 16 wk tenotomy and not significantly improved after repair. Peak isometric force reported here are greater than prior reports of rabbit SSP force after tenotomy. Peak stress was not significantly different between groups and consistent with prior literature of SSP stress. Muscle strain during contraction was significantly decreased after 8 wk of tenotomy and repair, indicating effects of tear and repair on muscle function. The experimental length-tension data were overlaid with predicted curves for each experimental group (generated from structural data), exposing the altered structure-function relationship for tenotomy and repair over time. Data presented here contribute to understanding the physiological implications of disease and repair in the rotator cuff.NEW & NOTEWORTHY We utilize an established method to measure the length-tension relationship for the rabbit supraspinatus in normal, torn, and repaired muscles. We then perform architectural analysis to evaluate structural changes after tear and repair. Although peak isometric force is lower in the tear and repair groups, there are no differences in peak stresses across groups. These findings indicate persistent structural changes (both radial and longitudinal atrophy) and physiological deficiencies (decreased peak force and uncoupling structure-function relationship) after tenotomy that do not significantly recover after repair.

The Impact of the COVID-19 Pandemic on Occupational Stress in Restaurant Work: A Qualitative Study.

The economic downturn due to the COVID-19 pandemic disproportionately impacted the food service industry-one of the largest workforce sectors in the United States. The purpose of this qualitative study was to explore the occupational stressors experienced by restaurant and food service workers during the COVID-19 pandemic through a detailed assessment of their lived experiences. Thematic analysis was used to identify patterns within data from sixteen semi-structured interviews with people employed or recently employed in the restaurant industry during July of 2020. Five themes were highlighted including fear of being exposed to the COVID-19 virus while working under inadequate safety policies, job insecurity, inconsistent pay and hours and a lack of health benefits and paid time off, all of which increased occupational stress and led to uncertainty if respondents would return to the restaurant industry. Hardships associated with the pandemic were mitigated by the support and connections fostered by the communities built within the restaurants. Results led to several recommendations to address the social and economic contributors to occupational stress at the structural and population levels which can be used in the current and post-pandemic workplace.

Relationship between behavioral inhibition and approach motivation systems (BIS/BAS) and intrinsic brain network connectivity in adult cannabis users.

Dampened behavioral inhibition and overactive behavioral approach motivation systems (i.e. BIS/BAS) are associated with cannabis use disorder (CUD), although the underlying neural mechanisms of these alterations have not yet been examined. The brain's executive control network (ECN) plays a role in decision-making and is associated with BIS/BAS. In this study, we tested the hypothesis that altered ECN resting-state functional connectivity (rsFC) underlies dysfunctional behavioral inhibition and approach motivation in cannabis users. To that end, we collected resting-state functional magnetic resonance imaging scans in 86 cannabis using adults and 59 non-using adults to examine group differences in the relationship between ECN rsFC and BIS/BAS. Our results showed that BIS was positively correlated with left ECN rsFC in cannabis users, while it was positively correlated with right ECN rsFC in non-users. There was a trend-level moderation effect of group on the association between BIS/BAS and ECN rsFC, showing a weaker association in BIS/BAS and ECN rsFC in cannabis users compared to non-users. An exploratory mediation analysis found that the severity of CUD mediated the relationship between users' BIS scores and left ECN rsFC. These findings suggest that cannabis use may lead to dysregulation in typical ECN functional organization related to BIS/BAS.

Regional heterogeneity in coral species richness and hue reveals novel global predictors of reef fish intra-family diversity.

Habitat heterogeneity shapes biological communities, a well-known process in terrestrial ecosystems but substantially unresolved within coral reef ecosystems. We investigated the extent to which coral richness predicts intra-family fish richness, while simultaneously integrating a striking aspect of reef ecosystems-coral hue. To do so, we quantified the coral richness, coral hue diversity, and species richness within 25 fish families in 74 global ecoregions. We then expanded this to an analysis of all reef fishes (4465 species). Considering coral bleaching as a natural experiment, we subsequently examined hue's contribution to fish communities. Coral species and hue diversity significantly predict each family's fish richness, with the highest correlations (> 80%) occurring in damselfish, butterflyfish, emperors and rabbitfish, lower (60-80%) in substrate-bound and mid-water taxa such as blennies, seahorses, and parrotfish, and lowest (40-60%) in sharks, morays, grunts and triggerfish. The observed trends persisted globally. Coral bleaching's homogenization of reef colouration revealed hue's contribution to maintaining fish richness, abundance, and recruit survivorship. We propose that each additional coral species and associated hue provide added ecological opportunities (e.g. camouflage, background contrast for intraspecific display), facilitating the evolution and co-existence of diverse fish assemblages.

Residual Effects of Cannabis Use on Effort-Based Decision-Making.

OBJECTIVE: Acute Δ9-tetrahydrocannabinol (THC) administration in humans (Lawn etal., 2016) and rats (Silveira, Adams, Morena, Hill, & Winstanley, 2016) has been associated with decreased effort allocation that may explain amotivation during acute cannabis intoxication. To date, however, whether residual effects of cannabis use on effort-based decision-making are present and observable in humans have not yet been determined. The goal of this study was to test whether prolonged cannabis use has residual effects on effort-based decision-making in 24-hr abstinent cannabis using adults. METHOD: We evaluated performance on the Effort Expenditure for Reward Task (EEfRT) in 41 adult cannabis users (mean age = 24.63 years, 21 males) and 45 nonusers (mean age = 23.90 years, 19 males). A mixed 2x3x3 ANOVA with age as a covariate was performed to examine the effect of group, probability of winning, and reward amount on EEfRT performance. EEfRT performance was operationalized as % of trials for which the hard (vs. easy) condition was chosen. Pearson's correlations were conducted to test the relationship between EEfRT performance and measures of cannabis use, anhedonia and motivation. RESULTS: We found that cannabis users selected hard trials significantly more than nonusers regardless of win probability or reward level. Frequency of cannabis use was positively correlated with amount of % hard trials chosen. There were no significant correlations between % hard trials chosen, self-reported anhedonia, or motivation. CONCLUSIONS: These results suggest that unlike acute effects, residual effects of cannabis following 24 hrs of abstinence are associated with greater effort allocation during effort-based decision-making.

Geographic Heterogeneity in Influenza and Pneumonia Mortality in Hispanic Americans.

(1) Background: Influenza and pneumonia (IP) is a leading cause of death in the US. The hypothesis was tested that the mortality rate differential between Hispanic whites (HW) and non-Hispanic whites (NHW) from IP varied by geographic region in the US. (2) Methods: The CDC database for multiple causes of death between 1999-2018 was used for this study. For ages 25-84, age-adjusted mortality rates per 100,000 (AAMR) for IP were computed by Hispanic ethnicity in whites for 10 Health & Human Services (HHS) regions and for urbanization levels in HHS Region 2. (3) Results: AAMR for IP was 13.76 (13.62-13.9) in HW and 14.91 (14.86-14.95) in NHW (rate ratio 1.08). Among HHS regions, rates were generally lower in HW than in NHW with the major exception of HHS Region 2. The rate there was 21.78 (21.24-22.33) in HW, 36.5% greater (p < 0.05) than that in NHW of 15.71 (15.56-15.86). In large central metro areas of Region 2, the rate was 27.10 (26.36-27.83) in HW compared to 19.78 (19.47-20.09) in NHW. (4) Conclusion: The difference in AAMR from IP between HW and NHW varied by region and urbanization with much higher rates for HW than NHW only in metropolitan areas of New York and New Jersey.

In vivo supraspinatus muscle contractility and architecture in rabbit.

The rotator cuff (RC) muscles are crucial in moving and stabilizing the glenohumeral joint, and tears can be functionally devastating. Chronic fatty and fibrotic muscle changes, which are nonresponsive to surgical tendon repair, are a focus of contemporary research. The rabbit model recapitulates key biological features of human RC tears, but function and physiology are poorly characterized; limited force and stress data are inconsistent with literature norms in other mammalian species. Here, we present an improved method to assess the physiology of the rabbit supraspinatus muscle (SSP), and we report values for healthy SSP architecture and physiology. Using female New Zealand White Rabbits (n = 6) under 2% isoflurane anesthesia, we surgically isolated the SSP and maximum isometric force measured at 4-6 muscle lengths. Architectural analysis was performed, and maximum isometric stress was computed. Whole muscle length-tension curves were generated using architectural measurements to compare experimental physiology to theoretical predictions. Maximum isometric force (80.87 ± 5.58 N) was dramatically greater than previous reports (11.06 and 16.1 N; P < 0.05). Architectural measurement of fiber length (34.25 ± 7.18 mm), muscle mass (9.9 ± 0.93 g), pennation angle (23.67 ± 8.32°), and PCSA (2.57 ± 0.20 cm2) were consistent with prior literature. Isometric stress (30.5 ± 3.07 N/cm2) was greater than previous reports of rabbit SSP (3.10 and 4.51 N/cm2), but similar to mammalian skeletal muscles (15.7-30.13 N/cm2). Previous studies underestimated peak force by ∼90%, which has profound implications for interpreting physiological changes as a function of disease state. The data that are presented here enable understanding the physiological implications of disease and repair in the RC of the rabbit.NEW & NOTEWORTHY We introduce an improved method to assess rabbit supraspinatus muscle physiology. Maximum isometric force measured for the rabbit supraspinatus was dramatically greater than previous reports in the literature. Consequently, the isometric contractile stress reported is almost 10 times greater than previous reports of rabbit supraspinatus, but similar to available literature of other mammalian skeletal muscle. We show that previous reports of peak supraspinatus isometric force were subphysiological by ∼90.

Using NMR Spectroscopy To Measure Protein Binding Capacity on Gold Nanoparticles.

A simple one-dimensional 1H NMR experiment that quantifies protein bound to gold nanoparticles has been developed for upper-division biochemistry and physical chemistry students. This laboratory experiment teaches the basics of NMR techniques, which is a highly effective tool in protein studies and supports students to understand the concepts of NMR spectroscopy and nanoparticle-protein interactions. Understanding the interactions of gold nanoparticles (AuNPs) with biological macromolecules is becoming increasingly important as interest in the clinical use of nanoparticles has been on the rise. Applications in drug delivery, biosensing, diagnostics, and enhanced imaging are all tangible possibilities with a better understanding of AuNP-protein interactions. The ability to use AuNPs as biosensors for drug delivery methods in cellular uptake is dependent on the amount of protein that is able to bind to the surface of the nanoparticle. This laboratory experiment solidifies concepts such as quantitative NMR spectroscopy while reinforcing precision laboratory titrations. Students learn how 1H proton NMR spectra can be used to measure free protein in solution and protein bound to AuNPs. A simple formula is used to determine the binding capacity of the nanoparticle. This analysis helps students to understand the impact of nanoparticle-protein interactions, and it allows them to conceptualize macromolecular binding using NMR spectroscopy.