Recovery Studies Research Articles

2024 Update of the RECOVER-Adult Long COVID Research Index.

Classification of persons with long COVID (LC) or post-COVID-19 condition must encompass the complexity and heterogeneity of the condition. Iterative refinement of the classification index for research is needed to incorporate newly available data as the field rapidly evolves. To update the 2023 research index for adults with LC using additional participant data from the Researching COVID to Enhance Recovery (RECOVER-Adult) study and an expanded symptom list based on input from patient communities. Prospective, observational cohort study including adults 18 years or older with or without known prior SARS-CoV-2 infection who were enrolled at 83 sites in the US and Puerto Rico. Included participants had at least 1 study visit taking place 4.5 months after first SARS-CoV-2 infection or later, and not within 30 days of a reinfection. The study visits took place between October 2021 and March 2024. SARS-CoV-2 infection. Presence of LC and participant-reported symptoms. A total of 13 647 participants (11 743 with known SARS-CoV-2 infection and 1904 without known prior SARS-CoV-2 infection; median age, 45 years [IQR, 34-69 years]; and 73% were female) were included. Using the least absolute shrinkage and selection operator analysis regression approach from the 2023 model, symptoms contributing to the updated 2024 index included postexertional malaise, fatigue, brain fog, dizziness, palpitations, change in smell or taste, thirst, chronic cough, chest pain, shortness of breath, and sleep apnea. For the 2024 LC research index, the optimal threshold to identify participants with highly symptomatic LC was a score of 11 or greater. The 2024 index classified 20% of participants with known prior SARS-CoV-2 infection and 4% of those without known prior SARS-CoV-2 infection as having likely LC (vs 21% and 5%, respectively, using the 2023 index) and 39% of participants with known prior SARS-CoV-2 infection as having possible LC, which is a new category for the 2024 model. Cluster analysis identified 5 LC subtypes that tracked quality-of-life measures. The 2024 LC research index for adults builds on the 2023 index with additional data and symptoms to help researchers classify symptomatic LC and its symptom subtypes. Continued future refinement of the index will be needed as the understanding of LC evolves.

Does Language Ability Predict Natural Recovery From Stuttering?

Purpose: This review article examines the proposal that language ability is a predictor or associate of natural recovery from stuttering. Specifically, this is the claim that preschool children who stutter (CWS) but have strong language skills are more likely to recover from this disorder naturally (without professional treatment) than those who have weaker language skills. Method: Studies that investigated this proposal are described, and their findings are reported in an effort to achieve greater clarity regarding this claim. The review includes studies that were published in peer-reviewed research journals in English since 1996. Results: Collectively, studies of language ability and natural recovery from stuttering have yielded mixed results. Although some studies found evidence to support an association, others did not, and still others yielded only partial support. Possible explanations for the complex and inconsistent findings are discussed, and suggestions are offered for speech-language pathologists who work with CWS. Conclusions: Language ability in preschool children is not a consistent or robust predictor or associate of natural recovery from stuttering. For this reason, it is risky to assume that a young child who stutters but has strong language skills is likely to recover from stuttering naturally and therefore does not require professional treatment for this disorder.

Continuous-flow analysis of nitrogen compounds in environmental water using a copper–zinc reduction coil

The copper–cadmium reduction method has been applied to determine nitrogen compounds in heavily contaminated environmental water. However, there is an international demand to reduce the use of cadmium because it is harmful to humans and environment. Hence, a copper–zinc reduction continuous flow analysis system without using cadmium was developed for nitrogen‐compound determination. However, the effects of seawater contaminants on this analytical method remains unknown. Therefore, in this study, the effects of contaminants on the developed method are investigated, and the applicability of the method to environmental water analysis is examined. Resultantly, interference due to magnesium precipitation is confirmed; however, this could be prevented by adjusting the concentration of the analytical reagent, i.e,. ethylenediaminetetraacetic acid disodium. The measurement of certified reference materials under the new conditions, with precipitation countermeasures, show good results, with an accuracy of over 96%. Additionally, a recovery study using actual environmental water afforded good results, with recovery of >95% for all samples. These results indicate that the proposed method is an excellent, cadmium-free analytical method capable of analyzing environmental water as effectively as conventional methods.

Mechanism Study of Hot Carrier Degradation Recovery by Gate Induced Drain Leakage in 14 nm nFinFET

Mechanism Study of Hot Carrier Degradation Recovery by Gate Induced Drain Leakage in 14 nm nFinFET

Large animal models enhance the study of crypt-mediated epithelial recovery from prolonged intestinal ischemia reperfusion injury.

Intestinal ischemia and reperfusion injury (IRI) is a deadly and common condition. Death is associated with sepsis due to insufficient epithelial repair, requiring stem cell-driven regeneration, typically beginning 48 h after injury. Animal models are critical to advancing this field. To effectively study epithelial healing, models must survive clinically relevant intestinal ischemic injury extending to the crypt. Although mouse models are indispensable to intestinal research, their application for studying epithelial repair following severe IRI may be limited. Ischemic injury was induced in mouse and porcine jejunum for up to 3 h, with up to 72 h of reperfusion. Histologic damage was scored by Chiu-Park grade, and animal survival was assessed. Findings were compared between species. A mouse IRI literature review was performed to evaluate the purported degree of injury, duration of recovery, and reported survival rates. In mice and pigs, 3 h of ischemia induced severe, reliable injury extending into the crypt. However, at 48 h, mouse survival was only 23.5% compared with 100% survival in pigs. In literature, ischemia was induced for >1 h in only 4 of 102 mouse studies and none to 3 h. Recovery was attempted for 48 h in only six reports. Forty-seven studies reported intestinal crypt injury. Of those that featured histologic intestinal crypt damage, survival rates at 48 h ranged from 10 to 50% (median 30%). Mouse models are not ideal for studying intestinal stem cell-mediated recovery from severe IRI. Alternative large animal models, like pigs, are recommended.NEW & NOTEWORTHY Additional research is needed to improve recovery from severe intestinal ischemia. The selection of the ideal animal model is critical to facilitating this work. Based on our experimentation and literature review, porcine models, with increased translatability and an improved ability to survive both prolonged ischemia and the recovery period, appear to be the most appropriate choice for future studies.

Study of the selective zinc recovery from spent alkaline batteries using a multi-step ammonium carbonate and ammonium hydroxide-based leaching

Study of the selective zinc recovery from spent alkaline batteries using a multi-step ammonium carbonate and ammonium hydroxide-based leaching

Clinical relevance of current patient-reported outcome measures for ankle fracture: surgeons' perspective.

Determine the relevance of the most frequently used patient-reported outcome measures (PROMs) for monitoring patient recovery after ankle fracture, from the clinical perspective of orthopaedic trauma surgeons, given lack of validated PROMs. Prospective cohort. Orthopaedic Trauma Association committee meetings, electronic correspondence. Orthopaedic trauma surgeons. Delphi method for consensus activities. IV. Most clinically relevant PROMs for ankle fracture recovery. Several English-language PROMs were identified based on use in literature and relevance to ankle fractures. 7 were selected by expert consensus. These are the Ankle Fracture Outcome of Rehabilitation Measure (A-FORM), Foot and Ankle Ability Measure (FAAM), American Academy of Orthopaedic Surgeons (AAOS), Foot and Ankle Disability Index (FADI) Score, Lower Extremity Functional Scale (LEFS), Olerud-Molander Ankle Score (OMAS), and Patient-Reported Outcome Measurement Information System Physical Function (PROMIS PF). The most clinically relevant PROM is the A-FORM, followed by the AAOS, LEFS, PROMIS PF, FADI, and OMAS, and the least clinically relevant overall, the FAAM. Understanding which PROM best matches physician expectations for tracking recovery is an important step toward a robust, evidence-based approach to patient care. The A-FORM was identified as the most clinically relevant among the most used PROMs. These results will aid surgeons, clinicians, and scientists to identify a uniformly, clinically relevant PROM for the treatment and study of outcomes and recovery after isolated ankle fracture.

Development and validation of a UV spectrophotometric method for simultaneous estimation of teneligliptin hydrobromide hydrate and pioglitazone hydrochloride in pharmaceutical dosage form

BackgroundThis study presents the development and validation of a UV spectrophotometric method for the simultaneous estimation of teneligliptin hydrobromide hydrate (TEN) and pioglitazone hydrochloride (PIO) in pharmaceutical dosage forms. The method measures absorbance at 243 nm for TEN and 265 nm for PIO. Validation was conducted according to ICH guidelines, covering specificity, linearity, range, precision, accuracy, limit of detection, limit of quantification, and robustness.ResultsThe method exhibited linearity in the 2–25 µg/ml concentration range for both TEN and PIO, with correlation coefficients close to 1. Precision studies showed low % RSD values, indicating excellent repeatability and minimal intra- and inter-day variability. Accuracy was confirmed through recovery studies, with results within the 98–102% range. The method demonstrated sensitivity with low LOD and LOQ values. Robustness testing showed stability and consistency under varying conditions. Analysis of tablet formulations confirmed the accurate quantification of both drugs.ConclusionThe developed UV spectrophotometric method offers a simple, sensitive, and cost-effective solution for the simultaneous estimation of TEN and PIO in pharmaceutical formulations. It is suitable for routine analysis and quality assessment of tablet dosage forms.

Agile monitoring dashboard for clinical research studies

BackgroundClinical trial success hinges on efficient participant recruitment and retention. However, slow accrual and attrition frequently hinder progress. To address these challenges, a novel dashboard tool with control charts has been developed to provide investigators on the multi-site study of Delirium and Neuropsychological Recovery among Emergency General Surgery Survivors (DANE study) with timely information to improve trial recruitment.MethodsA quality monitoring Excel dashboard with control chart functionality developed by the principal investigator’s (PI) group and implemented in a department of a large hospital was re-engineered for research study recruitment purposes. The dashboard provides the PIs and other stakeholders with timely, actionable, and unbiased information on the count of participants who have completed each stage or action within the process, the rates of completion and trends, both for the current week and cumulatively.ResultsThe DANE dashboard was prototyped using Microsoft Excel for accessibility and rapid development. The tool integrates with a REDCap database, simplifying data import and analysis. By facilitating informed decision-making throughout the recruitment process, the DANE dashboard has significantly enhanced clinical trial efficiency and led to changes in the eligibility criteria and improvements in the approach and consent processes.ConclusionsThe DANE dashboard for monitoring participant recruitment and attrition in research studies represents a significant step towards enhancing study management and decision-making processes. It can be adapted to other clinical studies and other staged processes with attrition. The generic version, currently under development, holds promise for evolving into a valuable simulator by incorporating a spreadsheet for generating random data and accounting for resource constraints. This enhancement could further be augmented by integrating forecasting capabilities into the control charts.Trial registrationThe Delirium and Neuropsychological Recovery among Emergency General Surgery Survivors (DANE) study (NCT05373017, 1R01AG076489-01) is a multi-site, two-arm, single-blinded randomized controlled clinical trial to evaluate the efficacy of the Emergency General Surgery (EGS) Delirium Recovery Model to improve the cognitive, physical, and psychological recovery of EGS delirium survivors over 65. The DANE study received approval from the University of Wisconsin-Madison/University of Wisconsin Hospitals and Clinics Institutional Review Board (IRB, no. 2022–0545, approval date September 14, 2022), and Indiana University agreed to cede IRB review to University of Wisconsin-Madison/University of Wisconsin Hospital and Clinics (September 29, 2022).

Structural and Functional Implications of Polyarginine Addition to Green Fluorescent Protein Expression in Saccharomyces cerevisiae INVSc1

Green Fluorescent Protein (EGFP) is widely used as a reporter gene, aiding in protein recovery and transduction studies. In this study, EGFP was tagged with eleven arginine residues (PolyR) and six histidine residues (His-tag) for purification. The aim was to enhance the synthesis of EGFP-PolyR in Saccharomyces cerevisiae and evaluate the effects of polyarginine modification on protein stability and expression levels. The expression of EGFP and EGFP-PolyR in S. cerevisiae was assessed through fluorescence measurements and protein levels. Structural analyses were conducted using in silico tools to investigate changes in beta strands and helices, which were validated through Western blots. Results showed that EGFP-PolyR maintained similar fluorescence levels to EGFP, but with notable structural changes. EGFP-PolyR's final beta strand terminates at Ala228, compared to Gly229 in EGFP, affecting the beta sheet's stability. Structural modifications also included altered helix lengths, with a longer helix 10 and shorter helix 9 in EGFP-PolyR. These alterations, along with shifts in helix-helix interactions, contribute to destabilization. Additionally, EGFP-PolyR exhibited unique gamma coils absent in EGFP, further differentiating its structure. The structural changes led to decreased protein expression and solubility, as indicated by Western blot analysis, with EGFP-PolyR showing significantly lower expression levels. The findings suggest that EGFP-PolyR is prone to aggregation and misfolding, characteristics often associated with aggregation-prone proteins.In conclusion, the polyarginine modification significantly impacts the structural integrity, stability, and solubility of EGFP. While fluorescence is retained, these changes hinder protein detectability and purification, highlighting the importance of considering structural alterations when modifying reporter proteins for experimental use.

Electrochemical Determination of 17‐α‐Ethinylestradiol on a Graphene Quantum Dots and Carbon Black Modified Glassy Carbon Electrode

A simple and inexpensive electrochemical sensor based on a glassy carbon electrode modified with graphene quantum dots and carbon black nanoparticles (GQDs‐CB‐DHP/GCE) was applied to determine emerging contaminant estrogen 17‐α‐ethinylestradiol (EE2). The combination of this nanocomposite with the GCE has not yet been explored as an electrochemical sensor. Combined, these materials create a synergy that enhances the overall performance of the oxidative detection system, resulting in a more efficient and accurate detection. The analytical curve presented a linear dynamic range from 0.998 to 10.0 µmol L <sup>‐1</sup>, with a detection limit of 0.998 µmol L <sup>‐1</sup>. Addition and recovery studies were carried out on a lake water sample, showing a recovery of 92.3%. The accuracy of the developed method was also evaluated by determining EE2 in pharmaceutical formulation samples. The obtained results were in statistical agreement with those obtained using HPLC‐DAD at a confidence level of 95%. Therefore, the electrochemical sensor developed presented a fast construction procedure and the electroanalytical method for EE2 determination proved to be precise and accurate, with low consumption of reagents and a low relative cost.

Optimization of Microwave-Assisted Organosolv Cellulose Recovery from Olive-Tree Pruning with Three Different Solvents

Research studies for cellulose recovery from lignocellulosic materials are essential in order to propose sustainable alternatives to harness residual biomasses, solving problems caused by their abundance and inadequate use. In this study, olive-tree pruning biomass has been subjected to different pretreatments with different organosolvents (acetone, ethanol, and γ-valerolactone) with microwave radiation assistance. The effect of operating parameters has been studied, considering specific ranges of variables values according to each experimental design but, in any case, located in the ranges of 33–67% (chemical compound concentration), 130–170 °C (temperature), 5–30 min (reaction time), and 1/20–1/5 (solid/liquid ratio, s/L). Based on the R2 and R2adj values (mostly above 0.97), the experimental data were adequately adjusted to four selected response variables: post-solids cellulose and lignin content apart from removal percentages of both structural components. The optimization process resulted in post-treatment solids with meaningful cellulose yields (higher than 84.7%) and reduced lignin content (lower than 4.2%). The best results were obtained using 66.5% acetone (155 °C, 8.4 min and s/L = 1/19), involving greater material deconstruction, a high percentage of delignification (96.7%), not very significant cellulose loss (29.4%), and a post-treatment solid consisting almost exclusively of cellulose (≈99%).

A Novel Fluorescent Chemosensor for Sensitive and Rapid Determination of Pb(II) Ions in Aqueous Environments.

This investigation devised an eco-friendly spectrofluorometric Pb(II) ion measurement approach. To determine Pb(II) ions, a polymeric fluorescence sensor membrane with excellent selectivity has been developed. It contains photoinitiators, functional monomers that can be cured under UV radiation, and cross-linking agents. After the characterization of the membrane, the most suitable parameters for the measurement of Pb(II) ions were determined. The measurement was performed in a short time-roughly 40s-at emission and excitation wavelengths of 488nm and 277nm, respectively, at pH 6.0. The developed method's detection limit was calculated as 1.42 × 10- 9 mol L- 1, and its calibration range was recorded as 4.83 × 10- 9 to 9.66 × 10- 8 mol L- 1. Recovery studies and the sensor's stability, lifetime, and repeatability have been evaluated. Real sample applications have been implemented using wastewater samples. The suggested approach may be used to quickly and accurately determine Pb(II) ions at low concentrations with good selectivity and sensitivity.

Advanced HPTLC Method Development for Silibinin Analysis in Nanoformulated Scaffolds: A Box-Behnken Approach.

Silibinin (silybin), a bioactive component derived from the seeds of milk thistle (Silybum marianum), is recognized for its diverse pharmacological properties, including antioxidant, anti-inflammatory, and hepatoprotective effects. Given its therapeutic significance, accurately quantifying silybin in various formulations is essential. High-performance thin-layer chromatography (HPTLC) is a powerful analytical technique frequently used for this purpose. In this study, an HPTLC method was validated according to the International Council for Harmonization (ICH) guidelines to determine the concentration of silybin. The design of experiments (DoE), specifically the Box-Behnken design, was employed to optimize and understand the influence of critical method variables. The HPTLC method validation was performed using silica gel F254 HPTLC plates. The variables investigated included the composition of the mobile phase (% v/v), saturation time (minutes), and temperature in degree Celsius (°C), with the Box-Behnken design for optimization. The mobile phase consisted of chloroform, acetone, and formic acid in a 7:2:1 (v/v) ratio. Both the formulated scaffold and standard drug were applied to the plates, which were then processed in a twin chamber. After development, the plates were scanned at 288 nm using the Camag TLC Scanner IV with Vision CATS software. The validated HPTLC method demonstrated a strong linear relationship within the silybin concentration range of 2-10 μg/mL. The limit of detection (LOD) and limit of quantification (LOQ) for silybin were determined to be 0.469 and 1.423 μg/mL, respectively. Recovery studies indicated that the method provided accurate quantification, with recovery rates ranging from 97.53% to 99.82%. These results confirm the method's high accuracy, outstanding linearity, and reliability for the quantification of silybin in formulations. The validated HPTLC method proved to be a reliable analytical tool for the quantification of silybin in various formulations, particularly those containing polymers. The method's strong linearity, precision, and accuracy align with the ICH guidelines, making it suitable for routine analysis in quality control laboratories. The use of the Box-Behnken design for method optimization highlights the importance of systematic experimentation in achieving robust analytical outcomes.

A behavioral choice analysis of the role of life events during early nonabstinent natural recovery from alcohol use disorder.

Prior research supported a behavioral choice analysis of the role of life events in posttreatment drinking among abstinence-seeking inpatients with alcohol use disorder (AUD). This study investigated the generality of those relationships among persons attempting "natural" recovery involving moderation drinking. We had two hypotheses: (1) The likelihood of drinking after an event would be related to the degree of alcohol-related disruption in the life-health area of the event. (2) Event-related drinking episodes would be quantitatively greater than event-unrelated episodes. Participants (N = 83) were from a larger integrated data set of prospective natural recovery studies of persons with AUD who had stopped heavy drinking and had 6-month follow-up reports of drinking and events; abstainers were excluded. Alcohol-related disruption before resolution was assessed in four domains (relationships, vocational/financial, living arrangements/legal, physical health). As predicted, postresolution event-related drinking was positively correlated with preresolution vocational/financial disruption (p < .01) and negatively correlated with preresolution physical health problems (p = .06). Event-related drinking episodes involved heavier drinking than event-unrelated episodes (p < .001). These findings indicate strong support for the generality of the latter relationship and qualified support for the generality of the former relationship. The different results in the two samples are attributed to differences in the evolution of their AUD recovery process and the decoupling of the event-drinking relationships. The behavioral choice framework suggests ways to improve the characterization of environmental variables in future recovery research. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Techno-economic feasibility study of ammonia recovery from sewage sludge digestate in wastewater treatment plants

Wastewater treatment plants play a vital role in resource recovery, particularly through biogas production, a key renewable energy source. Beyond biogas, the digestate from anaerobic digestion is rich in nutrients like ammonia. This study explored the feasibility of recovering ammonia from sewage sludge digestate using air stripping. The process was modeled using Aspen Plus® software, utilizing real data from As-Samra WWTP in Jordan. Various operational parameters, such as digestate feed flow, air flow rate, temperature, and pressure, were analyzed to optimize ammonia recovery. The results showed that with a feed flow rate between 10,000 and 30,000 kg/hr, ammonia recovery reached 85%, with production exceeding 100 kg/hr, where the effect of the flow rate appears mostly at elevated feeding temperatures. Increased air flow rates significantly boosted recovery, achieving 90% efficiency at 60 °C with 50,000 kg/h as air flow. Flashing pressure peaked at 1.5 bar, with 85% efficiency at 95 °C, while higher pressures yielded diminishing returns, stabilizing production around 106 kg/hr. The NaOH feed rate also influenced output, rising from 100 kg/hr at a 50 kg/hr feed rate to 107 kg/hr at 750 kg/hr, with recovery efficiency exceeding 85%. The economic analysis showed that the project had a payback period of 6.07 years, reflecting a reasonable recovery of the initial investment. The net present value was 122,924 USD over 15 years, with 8% amortization rate, indicating that the project created value beyond the initial cost. The internal rate of return was 14.23%, surpassing the discount rate and highlighting the project's financial attractiveness.

Dispersive solid phase extraction and quadruple isotope dilution–mass spectrometry combination for the accurate and sensitive quantification of capsaicin in pepper, domestic wastewater and human saliva samples by GC–MS system

In the presented study, reduced graphene oxide/Fe3O4 (rGO/Fe3O4) nanocomposites based dispersive solid phase extraction (DSPE) – gas chromatography–mass spectrometry (GC–MS) method was developed for the determination of capsaicin in domestic wastewater (DW), pepper (PP) and human saliva (HS) samples. All important parameters of the DSPE method affected the preconcentration factor were carefully optimized to achieve high signal to noise ratio for the analyte. After the optimization studies, the system analytical performance of DSPE-GC–MS system was evaluated using the aqueous standard solution of capsaicin. Limit of detection (LOD), limit of quantitation (LOQ) and dynamic range were figured out to be 0.54 µg/kg, 1.80 µg/kg and 2.66 – 487.35 µg/kg, respectively. Under the optimum experimental conditions, recovery studies were conducted with the spiked DW, PP and HS samples, and percent recovery results were recorded between 52.6 % and 183.6 % via matrix matching calibration strategy. After the implementation of ID4 strategy, percent recovery results for the spiked DW, PP and HS samples were calculated as 98.2 %–99.3 %, 99.7 %–100.7 % and 99.4 %–99.8 %, respectively. In addition, capsaicin content in Sivri (S)-PP, Kıl (K)-PP and Samandağ (SA)-PP samples were found to be 309.5 ± 11.8 mg/kg, 873.7 ± 26.7 mg/kg and 165.3 ± 5.1 mg/kg via DSPE-GC-ID4-MS method, respectively. As a result, the combination of quadruple isotope dilution (ID4) strategy and the DSPE-GC–MS method were successfully performed to boost the accuracy and precision of developed DSPE-GC–MS method.

Prospective study of urinary incontinence recovery following endoscopic enucleation of the prostate.

To investigate the clinical trajectories and identify risk factors linked to post-enucleation urinary incontinence (UI). In this prospective study (April 2020 to March 2022) at a single institution, 316 consecutive patients receiving endoscopic enucleation due to benign prostatic enlargement were included. Patient information and perioperative details were collected. Follow-ups, from 1 to 6 months, assessed postoperative UI using International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form and a four-item pad questionnaire, classified per International Continence Society definitions. Logistic regression analysed predictors at 1 week, while generalised estimating equation assessed risk factors from 1 to 3 months postoperatively. Patients with a median prostate volume of 57 mL underwent enucleation, with 22.5% experiencing postoperative UI at 1 week, 5.6% at 3 months, decreasing to 1.9% at 6 months. Multivariable analysis identified age (>80 years), specimen weight (>70 g), en bloc with anteroposterior dissection, and anal tone (Digital Rectal Examination Scoring System score <3) as potential factors influencing UI. Subgroup analysis revealed that specimen weight was associated with both continuous and stress UI. Anal tone was related to both other types and stress UI, while overactive bladder symptoms were associated with urge UI. In summary, our study elucidates transient risk factors contributing to temporary post-enucleation UI after prostatectomy. Informed decisions and personalised interventions can effectively alleviate concerns regarding postoperative UI.

Enhanced energy efficiency technologies in healthcare buildings: a case study of waste heat recovery from an optimized battery-integrated cogeneration system

Abstract Healthcare buildings face significant challenges in enhancing energy efficiency. Combined, heat and power (CHP) plants integrated with battery energy storage systems (BESS) offer a promising solution by meeting electric, thermal and cooling demands using a single fossil primary energy source. Starting from an optimized battery-integrated cogeneration plant, a comparative analysis of two waste heat recovery technologies in a hospital building context has been conducted in this study. Specifically, an ammonia-water absorption, power, and cooling (APC) system and an organic Rankine cycle (ORC) plant are examined, both powered by the waste heat recovered from exhaust gases of the natural gas internal combustion engine, operating in a cogenerative configuration. A control strategy is implemented to enhance the efficiency of the integrated systems, prioritizing either cooling or electric power production based on hourly demand within the hospital. The results highlight the integration of waste heat recovery technologies inside the optimized battery-integrated cogeneration is capable to reach a 20.1% and 18.82% in fossil primary energy saving (PES), respectively with the ORC and APC systems. However, the higher investment cost brings the simple payback (SPB) period of the configuration with the ORC plant to 3.5 years, compared to 3.3 years of the solution with the APC plant. The study shows the benefits of incorporating waste heat recovery technologies into cogeneration systems with energy storage system, providing valuable guidance for developing economically viable and eco-friendly solutions for managing energy in healthcare buildings.

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.