Slower Recovery Rate Research Articles

Engineering PLA-MXene nanocomposite with balanced mechanical properties for enhanced shape memory effect

Poly(lactic acid) (PLA) as shape memory material has gained attention due to its biocompatibility, biodegradability, and ease of processing by 3D printing. PLA’s environmentally friendly nature makes it an attractive candidate for sustainable and recyclable shape memory applications. However, PLA’s slow shape recovery rate and low shape fixation percentage hinder its applicability as shape memory material. In the present study, we report MXene-modified PLA (PLA/Mx) nanocomposite with enhanced shape memory effect. Solution processing methods mediated the loading of the MXene in the PLA matrix. Different samples were prepared by varying the weight% of the MXene in the PLA matrix. The structure and morphology of samples were analyzed by XRD and TEM characterization. Thermogravimetric analysis was performed to measure the thermal stability of the composite. Compared with pure PLA, with MXene loading, the PLA/Mx composites show an increase in thermal. The shape recovery study on PLA/Mx samples used temperature as an external stimulus. The PLA/Mx composite exhibited a significantly improved shape memory effect than the PLA alone. The study exhibits that a shape memory effect can be improved by tuning the MXene additive loading in the PLA matrix. The material shape recovery effect was validated by fabricating the spiral structure. The fast shape recovery time 3s and shape fixation/recovery of > 95% was observed for 1 wt% of PLA/Mx. The PLA/Mx composite is expected to contribute significantly to implementing innovative shape memory applications, particularly in the biomedical field for sutures, controlled drug release, and minimally invasive devices.

Mediterranean octocoral populations exposed to marine heatwaves are less resilient to disturbances.

The effects of climate change are now more pervasive than ever. Marine ecosystems have been particularly impacted by climate change, with marine heatwaves (MHWs) being a strong driver of mass mortality events. Even in the most optimistic greenhouse gas emission scenarios, MHWs will continue to increase in frequency, intensity and duration. For this reason, understanding the resilience of marine species to the increase of MHWs is crucial to predicting their viability under future climatic conditions. In this study, we explored the consequences of MHWs on the resilience (the ability of a population to resist and recover after a disturbance) of a Mediterranean key octocoral species, Paramuricea clavata, to further disturbances to their population structure. To quantify P. clavata's capacity to resist and recover from future disturbances, we used demographic information collected from 1999 to 2022, from two different sites in the NW Mediterranean Sea to calculate the transient dynamics of their populations. Our results showed that the differences in the dynamics of populations exposed and those not exposed to MHWs were driven mostly by differences in mean survivorship and growth. We also showed that after MHWs P. clavata populations had lower resistance and slower rates of recovery than those not exposed to MHWs. Populations exposed to MHWs had lower resistance elasticity to most demographic processes compared to unexposed populations. In contrast, the only demographic process showing some differences when comparing the speed of recovery elasticity values between populations exposed and unexposed to MHWs was stasis. Finally, under scenarios of increasing frequency of MHWs, the extinction of P. clavata populations will accelerate and their capacity to resist and recover after further disturbances will be hampered. Overall, these findings confirm that future climatic conditions will make octocoral populations even more vulnerable to further disturbances. These results highlight the importance of limiting local impacts on marine ecosystems to dampen the consequences of climate change.

Assessing downtown recovery rates and determinants in North American cities after the COVID-19 pandemic

North American downtowns are struggling to recover from the global COVID-19 pandemic. This study aims to investigate the varying rates of recovery experienced by downtown areas in the 66 largest cities of the United States and Canada. Leveraging Location-Based Services data extracted from mobile phone location trajectories, we assess the recovery rates in the 2023 post-pandemic period, juxtaposed against pre-pandemic 2019 levels. We find significant disparities in downtown recovery rates. Economic factors emerge as crucial determinants, where downtowns hosting a concentration of sectors with remote/hybrid work options – such as information, finance, professional services and management – displayed sluggish recovery. Conversely, downtowns with a focus on industries like accommodation, manufacturing, education, retail, construction, entertainment and healthcare exhibited greater resilience post pandemic. Furthermore, higher density, crime rates and education levels were correlated with slower recovery rates, as were harsher weather conditions and longer commuting times. Lower-density and auto-orientated downtowns demonstrated a swift rebound, even surpassing pre-pandemic activity levels. These findings underscore the necessity for tailored policies to bolster the revival of North American downtown areas.

Calibrating Tropical Forest Coexistence in Ecosystem Demography Models Using Multi‐Objective Optimization Through Population‐Based Parallel Surrogate Search

AbstractTropical forest diversity governs forest structures, compositions, and influences the ecosystem response to environmental changes. Better representation of forest diversity in ecosystem demography (ED) models within Earth system models is thus necessary to accurately capture and predict how tropical forests affect Earth system dynamics subject to climate changes. However, achieving forest coexistence in ED models is challenging due to their computational expense and limited understanding of the mechanisms governing forest functional diversity. This study applies the advanced Multi‐Objective Population‐based Parallel Local Surrogate‐assisted search (MOPLS) optimization algorithm to simultaneously calibrate ecosystem fluxes and coexistence of two physiologically distinct tropical forest species in a size‐ and age‐structured ED model with realistic representation of wood harvest. MOPLS exhibits satisfactory model performance, capturing hydrological and biogeochemical dynamics observed in Barro Colorado Island, Panama, and robustly achieving coexistence for the two representative forest species. This demonstrates its effectiveness in calibrating tropical forest coexistence. The optimal solution is applied to investigate the recovery trajectories of forest biomass after various intensities of clear‐cut deforestation. We find that a 20% selective logging can take approximately 40 years for aboveground biomass to return to the initial level. This is due to the slow recovery rate of late successional trees, which only increases by 4% over the 40‐year period. This study lays the foundation to calibrate coexistence in ED models. MOPLS can be an effective tool to help better represent tropical forest diversity in Earth system models and inform forest management practices.

What Is the Trajectory of Recovery in the Early Postoperative Period after the Big 3 Shoulder Surgeries? Comparative Analysis Using 3 Previous Prospective Studies.

(1) Background: The aims of this study were to compare serial changes in outcome measures in the early postoperative period after rotator cuff repair (RCR), anatomical total shoulder replacement (ATSR), and reverse total shoulder replacement (RTSR). (2) Methods: In total, 143 patients who underwent RCR (n = 47), ATSR (n = 46), and RTSR (n = 50) were included. The visual analogue scale (VAS) for pain, the activity of daily living (ADL) score, and the American Shoulder and Elbow Surgeons (ASES) score were completed. (3) Results: At 3 months, the recovery rate for the VAS pain score was 43.7% in the RCR, 89.1% in the ATSR, and 78.4% in RTSR. The recovery rate for the ADL score was 36.3%, 69.5%, and 76.4%. The recovery rate for ASES score was 40.9%, 79.5%, and 77.4%. For all outcome measures, a lower recovery rate was observed in the RCR group than in the ATSR and RTSR groups. At 6 months after surgery, the recovery rate for the VAS pain score was 69.9%, 100%, and 90.3%. The recovery rate for the ADL score was 66.8%, 92.8%, and 91.5%. The recovery rate for the ASES score was 68.7%, 96.5%, and 90.9%. (4) Conclusion: Compared with ATSR and RTSR, a slower recovery rate was observed for RCR, measured to be approximately 40% at 3 months and 70% at 6 months after surgery. Rapid improvement in pain and shoulder function was achieved after ATSR and RTSR, with a recovery rate of over 70% at 3 months and over 90% at 6 months after surgery.

Conservation-oriented management benefits the Black-faced Spoonbill, an endangered migratory waterbird

Active conservation management is crucial for maintaining and recovering populations of threatened species. Yet, there are remarkably few studies quantifying the benefits of conservation management and comparing ecological and anthropogenic influences on populations. We investigate these issues using the Black-faced Spoonbill Platalea minor as a case study. This species is an endangered migratory waterbird that garnered significant conservation attention along the East Asian-Australasian Flyway. Its global population has shown an upward trend recently, yet the speed of recovery has varied spatially. Understanding the species’ occurrence across wintering sites and the factors driving the geographical variation in recovery is vital for examining the benefits of management. In winter 2021–2022, we surveyed the occurrence and abundance of Black-faced Spoonbills and gathered data on environmental conditions across six important wintering sites in Taiwan and the Chinese mainland. Our results indicated a preference for larger wetlands with water depths of 10–20 cm. Birds were more likely to be present in wetlands receiving conservation management interventions. Wetlands with vegetated bunds and fewer artificial materials tended to attract larger flocks. The contribution of wetland size and conservation management aimed at increasing spoonbill abundance varied across regions, with a more significant positive effect of conservation management observed in Taiwan. Our results serve as a valuable reference for regional conservation planning and wetland management in wintering areas, aiding their long-term conservation. In line with this, we recommend increased conservation management efforts informed by our findings, particularly in regions with relatively slow recovery rates.

Slow recovery rates and spatial aggregation of Triatoma infestans populations in an area with high pyrethroid resistance in the Argentine Chaco

BackgroundThe emergence of pyrethroid resistance has threatened the elimination of Triatoma infestans from the Gran Chaco ecoregion. We investigated the status and spatial distribution of house infestation with T. infestans and its main determinants in Castelli, a municipality of the Argentine Chaco with record levels of triatomine pyrethroid resistance, persistent infestation over 2005–2014, and limited or no control actions over 2015–2020.MethodsWe conducted a 2-year longitudinal survey to assess triatomine infestation by timed manual searches in a well-defined rural section of Castelli including 14 villages and 234 inhabited houses in 2018 (baseline) and 2020, collected housing and sociodemographic data by on-site inspection and a tailored questionnaire, and synthetized these data into three indices generated by multiple correspondence analysis.ResultsThe overall prevalence of house infestation in 2018 (33.8%) and 2020 (31.6%) virtually matched the historical estimates for the period 2005–2014 (33.7%) under recurrent pyrethroid sprays. While mean peridomestic infestation remained the same (26.4–26.7%) between 2018 and 2020, domestic infestation slightly decreased from 12.2 to 8.3%. Key triatomine habitats were storerooms, domiciles, kitchens, and structures occupied by chickens. Local spatial analysis showed significant aggregation of infestation and bug abundance in five villages, four of which had very high pyrethroid resistance approximately over 2010–2013, suggesting persistent infestations over space-time. House bug abundance within the hotspots consistently exceeded the estimates recorded in other villages. Multiple regression analysis revealed that the presence and relative abundance of T. infestans in domiciles were strongly and negatively associated with indices for household preventive practices (pesticide use) and housing quality. Questionnaire-derived information showed extensive use of pyrethroids associated with livestock raising and concomitant spillover treatment of dogs and (peri) domestic premises.ConclusionsTriatoma infestans populations in an area with high pyrethroid resistance showed slow recovery and propagation rates despite limited or marginal control actions over a 5-year period. Consistent with these patterns, independent experiments confirmed the lower fitness of pyrethroid-resistant triatomines in Castelli compared with susceptible conspecifics. Targeting hotspots and pyrethroid-resistant foci with appropriate house modification measures and judicious application of alternative insecticides with adequate toxicity profiles are needed to suppress resistant triatomine populations and prevent their eventual regional spread.Graphical

Influence of Controlled Condition Ice Encasement of Creeping Bentgrass and Annual Bluegrass on Plant Recovery, Gas Evolution, and Metabolites

Two cool-season putting green turfgrass species, annual bluegrass and creeping bentgrass, are differential in ice encasement tolerance. Physiological mechanisms associated with creeping bentgrass ice encasement tolerance and annual bluegrass susceptibility are not understood. The objectives were to evaluate oxygen, ethylene, and CO2 content within the upper soil space of the plants while frozen and immediately after ice melt after 0, 5, 10, 20, and 28 days of ice encasement (2.54 cm of ice) in growth chamber conditions. Following ice melt, plant samples were separated into leaf, crown, and root tissues and used to evaluate carbohydrate and amino acid content. Annual bluegrass exhibited higher damage (slower recovery rates) on most sampling days compared with creeping bentgrass. The organs that were most damaged and exhibited a differential principal component analysis snapshot, were the leaf and crown tissues. Creeping bentgrass may preserve leaf and crown tissues for postwinter recovery whereas significant metabolic changes occur in annual bluegrass leaves and crowns. Creeping bentgrass retained total amino acids in leaves following ice encasement whereas total leaf amino acid levels declined in annual bluegrass. Specific carbohydrates and amino acids such as the ability to maintain high levels of fructose, asparagine, and proline may be important indicators of the tolerance to ice encasement stress. On the basis of more prominent carbohydrate and amino acid loss in leaves and crowns and higher levels of CO2 evolution, annual bluegrass may exhibit a higher metabolism and/or tissue damage during ice encasement compared with creeping bentgrass, which could reduce spring recuperative potential.

Preparation of Gradient Polyurethane and Its Performance for Flexible Sensors.

Flexible sensors are prone to the problems of slow recovery rate and large residual strain in practical use. In this paper, a polyurethane functional composite with a gradient change in elastic modulus is proposed as a flexible sensor to meet the recovery rate and residual strain without affecting the motion. Different hard and soft segment ratios are used to synthesize a gradient polyurethane structure. The conductive percolation threshold was obtained between 45 wt% and 50 wt% of flake silver powder. Both gradient polyurethane and gradient polyurethane composites demonstrated that gradient materials can increase the recovery rate and reduce residual strain. The gradient polyurethane composites had a tensile strength of 3.26 MPa, an elastic modulus of 2.58 MPa, an elongation at break of 245%, a sensitivity coefficient of 1.20 at 0-25% deformation, a sensitivity coefficient of 11.38 at 25-75% deformation, a rate of recovery of 1.95 s at a time, and a resistance to fatigue (over 1000 cycles at a fixed strain of 20% showed a stable electrical response). The sensing performance under different cyclic strain frequencies was also investigated. The process has practical applications in the field of wearable skin motion and health monitoring.

Seventy-five years of vegetation change after fire in Tasmanian alpine heathland

Context Alpine ecosystems are threatened by warming and an associated increase in fire frequency. There is a gap in our knowledge of succession in Tasmanian alpine heath more than 50 years after fire. The literature suggests that the alpine successional progression usually involves decreasing rates of change, decreasing differences among fire ages, ongoing transitions among shrub species, ongoing transitions from some lifeforms/species to others, and that warming results in increases in species richness. Aims We test for these tendencies up to 75 years from fire in alpine vegetation on kunanyi/Mount Wellington, Tasmania, Australia. Methods We documented the changes in vegetation structure and composition between 1998 and 2022 in plots on either side of an alpine fire boundary in the alpine heathland and used earlier data and observations to extend the record of change after fire to 75 years. We put these changes in the context of the only area of alpine vegetation that was not burnt in 1947 or later. Key results The area last burnt in 1947 exhibited declines in all lifeform covers between 1998 and 2022. All lifeforms except tall shrubs and mat shrubs declined in cover in the area last burnt in 1962. By 2022, shrub cover in the 1962-burnt area had not attained equivalence with the area last burnt in 1947. Herbs had the most dramatic decline in both fire-age classes. There were few shrub seedlings in 2022. All but six taxa, three being exotic, were observed in both the plots and previous broader surveys. Increases in species richness caused by the upward migration of lower-elevation species were not observed. The long-unburnt patch lacked the major dominant of the 1947-burnt plots, namely Orites acicularis, and was dominated by a gymnosperm absent from most of the mountain. Conclusions Succession follows the initial floristic composition model. The differences in trajectories from the 1947 and 1962 fires could possibly be due to desiccation or abrasion damage from increasing wind speeds and temperatures. There are strong indications of further potential change in the absence of fire. Implications The slow rate of recovery and its on-going nature emphasise the importance of keeping fire out of this vegetation type.

Predicting the distribution of megabenthic communities on deep-water seamounts with cobalt-rich crusts in the Magellan Seamount Chain in the northwestern Pacific ocean

Deep-water seamount ecosystems are sensitive to human activities and have a slow recovery rate after being disturbed. Bottom trawling and potential deep-sea mineral extraction could severely damage benthic communities on seamounts and seriously impact deep-sea ecosystems. Inadequate knowledge of the distribution of megabenthos on seamounts or their community structure hinders deep-sea conservation and management. In this study, based on a multidisciplinary dataset generated from recordings taken by human-occupied vehicle (HOV) and remotely operated vehicles (ROVs) along transects and environmental variables, a range of megabenthic morphotaxa were observed on two adjacent deep-water seamounts and predicted using species distribution models (SDMs). Accordingly, based on the predicted distribution of each morphotaxon, five distinct communities were identified through cluster analysis. The results of SDMs showed that environmental variables varyingly impacted the distribution of different morphotaxa, among which the average velocity and eastness direction of near-bottom currents, bathymetric position index (BPI), and backscatter intensity exerted the most significant influence on megabenthic distribution patterns. The distribution of five distinct communities showed a similarity of community composition on the two deep-water seamounts, suggesting a potential connectivity between the two seamounts. The distribution of communities revealed the spatial characteristics of vulnerability of deep-water seamounts at the community level, which could provide a direct basis for marine spatial planning of deep-sea ecosystems.

Substantially Accelerated Response and Recovery in Pd-Decorated WO3 Nanorods Gasochromic Hydrogen Sensor.

The development of hydrogen (H2) gas sensors is essential for the safe and efficient adoption of H2 gas as a clean, renewable energy source in the challenges against climate change, given its flammability and associated safety risks. Among various H2 sensors, gasochromic sensors have attracted great interest due to their highly intuitive and low power operation, but slow kinetics, especially slow recovery rate limited its further practical application. This study introduces Pd-decorated amorphous WO3 nanorods (Pd-WO3 NRs) as an innovative gasochromic H2 sensor, demonstrating rapid and highly reversible color changes for H2 detection. In specific, the amorphous nanostructure exhibits notable porosity, enabling rapid detection and recovery by facilitating effective H2 gas interaction and efficient diffusion of hydrogen ions (H+) dissociated from the Pd nanoparticles (Pd NPs). The optimized Pd-WO3 NRs sensor achieves an impressive response time of 14s and a recovery time of 1s to 5% H2. The impressively fast recovery time of 1s is observed under a wide range of H2 concentrations (0.2-5%), making this study a fundamental solution to the challenged slow recovery of gasochromic H2 sensors.

Variance reflects resilience to disturbance along a stress gradient: Experimental evidence from coastal marshes.

Quantifying ecosystem resilience to disturbance is important for understanding the effects of disturbances on ecosystems, especially in an era of rapid global change. However, there are few studies that have used standardized experimental disturbances to compare resilience patterns across abiotic gradients in real-world ecosystems. Theoretical studies have suggested that increased return times are associated with increasing variance during recovery from disturbance. However, this notion has rarely been explicitly tested in field, in part due to the challenges involved in obtaining long-term experimental data. In this study, we examined resilience to disturbance of 12 coastal marsh sites (five low-salinity and seven polyhaline [=salt] marshes) along a salinity gradient in Georgia, USA. We found that recovery times after experimental disturbance ranged from 7 to >127 months, and differed among response variables (vegetation height, cover and composition). Recovery rates decreased along the stress gradient of increasing salinity, presumably due to stress reducing plant vigor, but only when low-salinity and polyhaline sites were analyzed separately, indicating a strong role for traits of dominant plant species. The coefficient of variation of vegetation cover and height in control plots did not vary with salinity. In disturbed plots, however, the coefficient of variation (CV) was consistently elevated during the recovery period and increased with salinity. Moreover, higher CV values during recovery were correlated with slower recovery rates. Our results deepen our understanding of resilience to disturbance in natural ecosystems, and point to novel ways that variance can be used either to infer recent disturbance, or, if measured in areas with a known disturbance history, to predict recovery patterns.

Capture and discard practises associated with an ornamental fishery affect the metabolic rate and aerobic capacity of three-striped dwarf cichlids Apistogramma trifasciata.

Fishing causes direct removal of individuals from wild populations but can also cause a physiological disturbance in fish that are released or discarded after capture. While sublethal physiological effects of fish capture have been well studied in commercial and recreational fisheries, this issue has been overlooked for the ornamental fish trade, where it is common to capture fish from the wild and discard non-target species. We examined metabolic responses to capture and discard procedures in the three-striped dwarf cichlid Apistogramma trifasciata, a popular Amazonian aquarium species that nonetheless may be discarded when not a target species. Individuals (n= 34) were tagged and exposed to each of four treatments designed to simulate procedures during the capture and discard process: 1) a non-handling control; 2) netting; 3) netting +30seconds of air exposure; and 4) netting +60seconds of air exposure. Metabolic rates were estimated using intermittent-flow respirometry, immediately following each treatment then throughout recovery overnight. Increasing amounts of netting and air exposure caused an acute increase in oxygen uptake and decrease in available aerobic scope. In general, recovery occurred quickly, with rapid decreases in oxygen uptake within the first 30minutes post-handling. Notably, however, male fish exposed to netting +60seconds of air exposure showed a delayed response whereby available aerobic scope was constrained <75% of maximum until ~4-6hours post-stress. Larger fish showed a greater initial increase in oxygen uptake post-stress and slower rates of recovery. The results suggest that in the period following discard, this species may experience a reduced aerobic capacity for additional behavioural/physiological responses including feeding, territory defence and predator avoidance. These results are among the first to examine impacts of discard practises in the ornamental fishery and suggest ecophysiological research can provide valuable insight towards increasing sustainable practises in this global trade.

Time Course of Recovery From Different Velocity Loss Thresholds and Set Configurations During Full-Squat Training.

Cornejo-Daza, PJ, Villalba-Fernández, A, González-Badillo, JJ, and Pareja-Blanco, F. Time course of recovery from different velocity loss thresholds and set configurations during full-squat training. J Strength Cond Res 38(2): 221-227, 2024-The aims of the research were to examine the effects of (a) velocity loss (VL) thresholds and (b) set configuration, traditional or cluster, on time-course recovery. A randomized cross-over research design was conducted, in which 15 resistance-trained men performed 4 protocols consisting of 3 sets of 70% 1RM in full squat (SQ), differing in the VL incurred during the set assessed with a linear velocity transducer: (a) 20% (70-20), (b) 30% (70-30), (c) 40% (70-40), and in the set configuration (d) 20% of VL using a cluster methodology (70-CLU). Movement velocity against the load that elicited a 1 m·s -1 velocity at baseline measurements (V1-load) in SQ, countermovement jump (CMJ) height, and sprint time in 20 m (T20) were assessed at baseline (Pre) and postintervention (Post, 6 hour-Post, 24 hour-Post, and 48 hour-Post). The 70-20 protocol resulted in fewer total repetitions than the other protocols ( p = 0.001), whereas 70-CLU, 70-30, and 70-40 completed similar total repetitions. The 70-30 protocol significantly worsened T20 at 6 hours-Post, CMJ at 48 hours-Post, and V1-load at 6 hours-Post ( p < 0.05). The 70-40 protocol significantly impaired T20 at 6 hours-Post, and CMJ and V1-load at 24 hours-Post ( p < 0.05). No significant performance reductions were observed for 70-20 and 70-CLU at 6 hours-Post, 24 hours-Post, and 48 hours-Post. Protocols with higher VL resulted in more pronounced fatigue and a slower rate of recovery. Cluster sets (70-CLU) resulted in higher volume than protocols with a similar level of fatigue (70-20) and a quicker recovery than protocols with a similar volume (70-30 and 70-40).

Variations in 1-year Trajectories of Levels of Pain and Capability After Shoulder Arthroplasty Are Associated With Baseline Mental Health.

There is variability in the trajectories of pain intensity and magnitude of incapability after shoulder arthroplasty. A better understanding of the degree to which variation in recovery trajectories relates to aspects of mental health can inform the development of comprehensive biopsychosocial care strategies. (1) Do pain intensities at baseline and the trajectories during recovery differ between groups when stratified by mental health composite summary score, arthroplasty type, and revision surgery? (2) Do magnitudes of capability at baseline and the trajectories during recovery differ between these groups? We used a registry of 755 patients who underwent shoulder arthroplasty by a single surgeon at a specialized urban orthopaedic hospital that recorded the mental component summary (MCS) score of the Veterans RAND 12, a measure of shoulder-specific comfort and capability (American Shoulder and Elbow Surgeons [ASES] score, which ranges from 0 to 100 points, with a score of 0 indicating worse capability and pain and 100 indicating better capability and pain and a minimum clinically important difference of 6.4), and the VAS for pain intensity (range 0 [representing no pain] to 10 [representing the worst pain possible], with a minimum clinically important difference of 1.4) preoperatively, 2 weeks postoperatively, and 6 weeks, 3 months, 6 months, and 1 year after surgery. Forty-nine percent (368 of 755) of the patients were men, with a mean age of 68 ± 8 years, and 77% (585) were treated with reverse total shoulder arthroplasty (rTSA). Unconditional linear and quadratic growth models were generated to identify the general shape of recovery for both outcomes (linear versus quadratic). We then constructed conditional growth models and curves for pain intensity and the magnitude of capability showing mean baseline scores and the rates of recovery that determine the trajectory, accounting for mental health (MCS) quartiles, primary or revision arthroplasty, and TSA or reverse TSA in separate models. Because pain intensity and capability showed quadratic trends, we created trajectories using the square of time. Patients in the worst two MCS quartiles had greater pain intensity at baseline than patients in the best quartile (difference in baseline for bottom quartile: 0.93 [95% CI 0.72 to 1.1]; p < 0.01; difference in baseline for next-worst quartile: 0.36 [95% CI 0.16 to 0.57]; p < 0.01). The rates of change in recovery from pain intensity were not different among groups (p > 0.10). Patients with revision surgery had greater baseline pain (difference: 1.1 [95% CI 0.7 to 1.5]; p < 0.01) but no difference in rates of recovery (difference: 0.031 [95% CI 0.035 to 0.097]; p = 0.36). There were no differences in baseline pain intensity and rates of recovery between patients with reverse TSA and those with TSA (baseline pain difference: -0.20 [95% CI -0.38 to -0.03]; p = 0.18; difference in rate of recovery: -0.005 [95% CI -0.035 to 0.025]; p = 0.74). Patients in the worst two MCS quartiles had worse baseline capability than patients in the best quartile (difference in baseline for bottom quartile: -8.9 [95% CI -10 to -7.4]; p < 0.001; difference in baseline for the next-worst quartile: -4.9 [95% CI -6.4 to -3.4]; p < 0.01), with no differences in rates of recovery (p > 0.10). Patients with revision surgery had lower baseline capability (difference in baseline: -13 [95% CI -15 to -9.7]; p < 0.01), with a slower rate of recovery (difference in rate of recovery: -0.56 [95% CI -1.0 to -0.079]; p = 0.021). There were no differences in baseline capability or rates of recovery between TSA and reverse TSA. The observation that preoperative and 1-year comfort and capability are associated with mental health factors and with similar recovery trajectories reminds us that assessment and treatment of mental health is best considered an integral aspect of musculoskeletal care. Future studies can address how prioritization of mental health in musculoskeletal care strategies might reduce variation in the 1-year outcomes of discretionary surgeries such as shoulder arthroplasty. Level III, therapeutic study.

Sea star wasting syndrome reaches the high Antarctic: Two recent outbreaks in McMurdo Sound.

Sea star wasting syndrome (SSWS) can cause widespread mortality in starfish populations as well as long-lasting changes to benthic community structure and dynamics. SSWS symptoms have been documented in numerous species and locations around the world, but to date there is only one record of SSWS from the Antarctic and this outbreak was associated with volcanically-driven high temperature anomalies. Here we report outbreaks of SSWS-like symptoms that affected ~30% of individuals of Odontaster validus at two different sites in McMurdo Sound, Antarctica in 2019 and 2022. Unlike many SSWS events in other parts of the world, these outbreaks were not associated with anomalously warm temperatures. Instead, we suggest they may have been triggered by high nutrient input events on a local scale. Although the exact cause of these outbreaks is not known, these findings are of great concern because of the keystone role of O. validus and the slow recovery rate of Antarctic benthic ecosystems to environmental stressors.

SHOCK4: Utilizing Mechanical Circulatory Support and Immunomodulation for the Management of Fulminant Lymphocytic Myocarditis: Case Series

Purpose: Five consecutive patients with biopsy-proven lymphocytic myocarditis (LM) presented to our medical center with cardiogenic shock (CS) requiring Mechanical Circulatory Support (MCS) and Immunomodulatory therapy. We present our experience and highlight the variability of presentation and management strategies. Methods: Five consecutive patients presented to our center between 3/1/2022 and 12/1/2022 with acute onset ventricular dysfunction and CS (Table). One had an out-of-hospital cardiac arrest. Due to the fulminant presentation and lack of typical risk factors, there was high clinical suspicion for myocarditis. One patient had positive influenza A testing. Results: All patients were managed acutely with VA-ECMO with or without left ventricular ventilation. All patients underwent an endomyocardial biopsy which showed virus-negative LM. Immunomodulatory therapy strategies varied among patients. Our initial approach was Methylprednisolone for 3 days and IVIG for all. Moreover, for those with a slower rate of recovery, or continued high inflammatory markers, plasmapharesis was utilized in addition to prolonged prednisone and/or azathioprine courses (Table). Of the five subjects, two had myocardial recovery, one developed chronic myocarditis, one developed chronic heart failure, and one required a durable LVAD. Conclusion: Lymphocytic myocarditis is a rare inflammatory disorder of the heart characterized by mononuclear cellular infiltrate and ventricular dysfunction. Fulminant myocarditis is characterized by CS or cardiac arrest. Prompt diagnosis is critical because the prognosis and recovery are better than with nonspecific histological findings or giant cell myocarditis (1,2). Our series and others have demonstrated MCS key role in decreasing mortality while treating the myocardial consequences of inflammatory injury (5-7). While viral infections are the most common cause found in 30-40% of cases (1,3,4), only one patient in our series had an influenza A infection, and none had positive viral testing on the biopsy. We found no consistent history of COVID-19 infection or vaccination among the patients. There is no consensus on the best strategy for immunomodulatory therapy, and more extensive studies with long-term outcomes are needed.

The effects of size on exhaustive exercise and recovery in a marine sportfish, the red drum (Sciaenops ocellatus).

Recreational angling is an economically important activity in many communities around the world. One conservation strategy adopted to offset the population-level consequences of recreational angling is "catch-and-release" (CAR), which is the act of returning fish to the environment following an angling event. While an expansive literature has helped to generalize CAR best practices, species-specific validation of recovery profiles remains a crucial component of species-specific angling guidance. This study sought to define the injury and recovery profiles in the plasma and white muscle following exhaustive exercise in two size classes of a common Gulf of Mexico sportfish, the red drum (Sciaenops ocellatus). The two sizes included a "small" (20-30cm) and "slot" size (51-74cm), the latter of which is a common angling target. Both size classes showed a characteristic injury profile that consisted of significantly elevated muscle and plasma lactate, plasma osmolality and haematocrit, as well as decreased muscle ATP and phosphocreatine, and lowered plasma and muscle pH. In small fish, muscle metabolites returned to control values by 1h post-exercise and plasma metabolites returned to control between 3 and 6h post-exercise. In contrast, slot sized fish had recovery periods of ≥3h for all metabolites. The maximum injury effect size was also greater in the slot size class. These data suggest that while red drum conform to typical patterns of post-exercise recovery, larger trophy-sized fish may be more at risk to the ancillary effects of exhaustive exercise owing to greater exercise injury and slower recovery rates.

Tailoring the shape memory properties of silica nanoparticle infused photopolymer composites for 4D printing applications: A Taguchi analysis

The study aims to optimize the shape change response of the Shape Memory Photopolymer Composites (SMPPCs) through the use of the Taguchi method. The SMPPCs were created by blending of Soft Photopolymer Resin (SPPR) with Hard Photopolymer Resin (HPPR) in various weight fractions and reinforcing with Silica Nanoparticles (SNPs) at different weight percentages using a Masked Stereolithography (MSLA). The researchers measured the ability of the material to change its shape by determining its shape recovery time (T), fixity ratio (Rf), recovery ratio (Rr), and recovery rate (Vr). The results indicated that the fastest T was observed in unreinforced Blended Photopolymer Resin (BPPR) with 75 wt% SPPR and 25 wt% HPPR. However, when the BPPR was reinforced with 0.3 wt% SNPs, the T was slower. The use of SNPs as reinforcement resulted in excellent Rf, whereas higher weight percentages of SPPR led to better Rr. The weight percentage of SPPR was found to be the primary contributor to T, Rr, and Vr, while the weight percentage of SNPs played a significant role in Rf. The optimum parameters for T and Vr were A1/B3/C1, for Rf were A3/B1/C1, and for Rr were A2/B2/C1. The research findings indicate that reinforced BPPR has outstanding fixity ratios and it is more appropriate for applications that necessitate lengthier recovery and slower recovery rate. The inclusion of SNPs in BPPR increases the T and prolongs the temporary shape retention of the specimen. The generated regression models were validated through confirmation experiments, which yielded strong agreement.