Sleep and Daytime Function in People with Spinal Cord Injury.

Study Design: Cross-sectional cohort study. Objectives: To determine the role of sleep-disordered breathing (SDB), insomnia symptoms and sleep quality in the daytime function and quality of life of veterans with spinal cord injury (SCI). Setting: A Veterans Administration (VA) medical center in the Midwestern US. Methods: Thirty-eight male veterans with SCI (22 cervical, 16 thoracic; mean [SD] age = 62.9[9.5] years) completed baseline assessments within a larger clinical trial. Measures assessed sleep apnea severity (apnea-hypopnea index, AHI), insomnia symptoms (Insomnia Severity Index, ISI), self-reported sleep quality (Pittsburg Sleep Quality Index, PSQI), daytime sleepiness (Epworth Sleepiness Scale, ESS), fatigue (Flinders Fatigue Scale, FFS), depression (Patient Health Questionnaire-9 item, PHQ-9 excluding sleep item), functioning (Spinal Cord Independence Measure, SCIM), and quality of life (World Health Organization Quality of Life, WHOQOL-BREF). Bivariate correlations (alpha p<.05) were used to assess relationships between sleep (AHI, ISI, PSQI, ESS) and function (FFS, PHQ-9, SCIM, WHOQOL-BREF). Results: Mean AHI was 29.9(26.6), mean ISI was 9.38(6.2), mean PSQI was 9.0(4.6), and mean ESS was 7.0(5.2). There were no significant relationships between AHI and function measures. Significant relationships emerged between ISI and PHQ-9, some WHOQOL-BREF subscales, and SCIM as well as between PSQI and FFS, PHQ-9, and some WHOQOL-BREF subscales. Conclusions: Among Veterans with SCI, insomnia symptom severity and poor sleep quality were associated with worse functioning, whereas SDB severity was not. Insomnia and poor sleep quality represent modifiable contributors to poor daytime function. Research evaluating the impact of evidence-based insomnia treatments among individuals living with SCI is warranted.

The Caspase-Activated DNase drives inflammation and contributes to defense against viral infection.

Mitochondria react to infection with sub-lethal signals in the apoptosis pathway. Mitochondrial signals can be inflammatory but mechanisms are only partially understood. We show that activation of the caspase-activated DNase (CAD) mediates mitochondrial pro-inflammatory functions and substantially contributes to host defense against viral infection. In cells lacking CAD, the pro-inflammatory activity of sub-lethal signals was reduced. Experimental activation of CAD caused transient DNA-damage and a pronounced DNA damage response, involving major kinase signaling pathways, NF-κB and cGAS/STING, driving the production of interferon, cytokines/chemokines and attracting neutrophils. The transcriptional response to CAD-activation was reminiscent of the reaction to microbial infection. CAD-deficient cells had a diminished response to viral infection. Influenza virus infected CAD-deficient mice displayed reduced inflammation in lung tissue, higher viral titers and increased weight loss. Thus, CAD links the mitochondrial apoptosis system and cell death caspases to host defense. CAD-driven DNA damage is a physiological element of the inflammatory response to infection.

Facile synthesis of iron nanoparticles from Camellia Sinensis leaves catalysed for biodiesel synthesis from Azolla filiculoides.

Recent years have seen an increase in research on biodiesel, an environmentally benign and renewable fuel alternative for traditional fossil fuels. Biodiesel might become more cost-effective and competitive with diesel if a solid heterogeneous catalyst is used in its production. One way to make biodiesel more affordable and competitive with diesel is to employ a solid heterogeneous catalyst in its manufacturing. Based on X-ray diffraction (XRD) and Fourier Transform infrared spectroscopy (FTIR), the researchers in this study proved their hypothesis that iron oxide core-shell nanoparticles were generated during the green synthesis of iron-based nanoparticles (FeNPs) from Camellia Sinensis leaves. The fabrication of spherical iron nanoparticles was successfully confirmed using scanning electron microscopy (SEM). As a heterogeneous catalyst, the synthesised catalyst has shown potential in facilitating the conversion of algae oil into biodiesel. With the optimal parameters (0.5 weight percent catalytic load, 1:6 oil-methanol ratio, 60 °C reaction temperature, and 1 h and 30 min reaction duration), a 93.33% yield was attained. This may be due to its acid-base property, chemical stability, stronger metal support interaction. Furthermore, the catalyst was employed for transesterification reactions five times after regeneration with n-hexane washing followed by calcination at 650 °C for 3 h.

Electrospinning of poly(ethylene oxide)/glass hybrid nanofibres for anticounterfeiting encoding.

The use of photochromism to increase the credibility of consumer goods has shown great promise. To provide mechanically dependable anticounterfeiting nanofibres, it has also been critical to improve the engineering processes of authentication patterns. Mechanically robust and photoluminescent electrospun poly(ethylene oxide)/glass (PGLS) nanofibres (150-350 nm) immobilized with nanoparticles of lanthanide-doped aluminate (NLA; 8-15 nm) were developed using electrospinning technology for anticounterfeiting purposes. The provided nanofibrous membranes changed colour from transparent to green when irradiated with ultraviolet light. By delivering NLA with homogeneous distribution without aggregations, we were able to keep the nanofibrous membrane transparent. When excited at 365 nm, NLA@PGLS nanofibres showed an emission intensity at 517 nm. The hydrophobicity of NLA@PGLS nanofibres improved by raising the pigment concentration as the contact angle was increased from 146.4° to 160.3°. After being triggered by ultraviolet light, NLA@PGLS showed quick and reversible photochromism without fatigue. It was shown that the suggested method can be applied to reliably produce various anticounterfeiting materials.

Preparation of photoluminescent nano-biocomposite nacre from graphene oxide and polylactic acid.

Nano-biocomposites of inorganic and organic components wereprepared to produce long-persistent phosphorescent artificial nacre-like materials. Biodegradable polylactic acid (PLA), graphene oxide (GO), and nanoparticles (13-20 nm) of lanthanide-doped aluminate pigment (NLAP) were used in a simple production procedure of an organic/inorganic hybrid nano-biocomposite. Both polylactic acid and GO nanosheets were chemically modified to form covalent and hydrogen bonding. The high toughness, good tensile strength, and great endurance of those bonds were achieved by their interactions at the interfaces. Long-persistent and reversible photoluminescence was shown by the prepared nacre substrates. Upon excitation at 365 nm, the nacre substrates generated an emission peak at 517 nm. When ultraviolet light was shone on luminescent nacres, they displayed a bright green colour. The high superhydrophobicity of the generated nacres was obtained without altering their mechanical characteristics.

Prevalence of central sleep apnea among veterans and response rate to continuous positive airway pressure therapy.

Study Objectives: Sleep-disordered breathing (SDB) is common in the Veteran population. In this retrospective study, we investigated the prevalence of comorbid central and obstructive SDB and the response rate to PAP among Veterans. Methods: Veterans were screened from a single VA medical center who had polysomnography (PSG) study from 2017 to 2021 to ascertain the presence, severity, and type of SDB by measuring the apnea-hypopnea index (AHI) and central apnea index (CAI). Patients were excluded if they did not have complete studies (diagnostic and PAP titration studies). The inclusion criteria for these analyses were central sleep apnea (CSA) defined as AHI ≥ 10 events/hour and CAI ≥ 5 events/hour. Diagnostic "CSA only" was defined as AHI ≥ 10 events/hour and CAI ≥ 50% of AHI. "OSA only" was defined if AHI ≥ 10 events/hour and CAI < 5 events/hour. Comorbid central and obstructive sleep apnea (COSA) was defined if AHI ≥ 10 events/hour and CAI > 5 events/hour but < 50% of AHI. The responsiveness to PAP therapy was determined based on the CAI < 5 events/hour on the titration study. Results: A total of 90 patients met the inclusion criteria and from those 64 Veterans were found to have COSA (71%), 18 (20%) were CSA only, and 8 (9%) were OSA only. A total of 22 (24.4%) Veterans diagnosed with CSA or COSA were responsive to PAP therapy. Sixty days after treatment initiation, both responsive and nonresponsive groups had significant decreases in AHI and CAI (p < 0.05). Conclusions: Comorbid central and obstructive SDB is common among Veterans. The response to PAP therapy is suboptimal but improves over time.

Sleep health and quality of life in the Detroit Research on Cancer Survivors cohort.

PURPOSE: Sleep disturbances represent a modifiable target to improve quality of life and longer-term outcomes in cancer survivors. However, the association between sleep health and overall quality of life in African American cancer survivors has been poorly assessed, a population at increased risk for morbidity and mortality. METHODS: Seven hundred and eighteen Detroit Research on Cancer Survivors (ROCS) cohort participants completed a supplemental sleep survey at the time of enrollment, which included the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Insomnia Severity Index (ISI). Linear and logistic regression was used to evaluate the association between sleep and mental health, while block regression models were used to estimate the contribution of clustered factors to Health-Related Quality of Life (HRQOL). RESULTS: Nearly 60% of the cohort reported symptoms indicative of poor sleep quality on the PSQI, 15% reported excessive daytime sleepiness on the ESS, and 12% reported moderate to severe insomnia on the ISI. Survivors with elevated ISI scores reported FACT-G scores that were 17 points lower than those without symptoms of insomnia (95% CI: - 13.1, - 21.2). Poor sleep health accounted for the largest proportion of variability in FACT-G scores (R2 = 0.27) and change in R2 value (0.18) when compared to comorbidities, health behaviors, cancer-related factors, and demographics. CONCLUSIONS: Overall sleep health was significantly associated with poorer HRQOL and variability in FACT-G scores. Additional studies investigating a causal relationship between sleep and HRQOL are needed to determine whether sleep quality could affect disparities in cancer outcomes. IMPLICATIONS FOR CANCER SURVIVORS: Addressing sleep quality in cancer survivors may improve long-term health and HRQOL.

Fabrication of biodegradable and antibacterial films of chitosan/polyvinylpyrrolidone containing Eucalyptus citriodora extracts.

The main objective of this work is to develop biodegradable active films through the combination of the extracts with different solvents sourced from Eucalyptus citriodora leaves, with films made of chitosan (Cs) and polyvinylpyrrolidone (PVP). Chromatographic profiling investigations were carried out to examine the antibacterial characteristics of E. citriodora extracts before their direct incorporation into the polymer films. At this point, the potent antimicrobial properties of the phenol compounds and bioactive components demonstrated an antibacterial activity that was particularly noticeable at a hexane resolution. Different morphological characteristics were seen on films made from these solvent extracts, such as Cs/PVP-AE, Cs/PVP-EAE, and Cs/PVP-HE, when scanning electron microscopy was used. Numerous other outcomes of all the interactions between the extract particles and the film were shown by the pores defined by the Cs/PVP film's porous nature. The addition of the extracts, either alone or in combination, greatly enhanced the Cs/NC/PVP films' mechanical characteristics. It has also been shown that adding plant extracts greatly increased the antibacterial activity of these films. These findings reveal that Cs/PVP films loaded with extract may be utilized as more environmentally acceptable substitutes for possible food packaging application by increasing shelf life of food products.

Medication-Induced Central Sleep Apnea: A Unifying Concept.

Medication-induced central sleep apnea (CSA) is one of the 8 categories of causes of CSA but in the absence of awareness and careful history may be misclassified as primary CSA. While opioids are a well-known cause of respiratory depression and CSA, non-opioids medications including sodium oxybate, baclofen, valproic acid, gabapentin and ticagrelor are less well-recognized. Opioids-induced respiratory depression and CSA are mediated primarily by µ-opioid receptors, which are abundant in the pontomedullary centers involved in breathing. The non-opioid medications, sodium oxybate, baclofen, valproic acid and gabapentin, act upon brainstem gamma-aminobutyric acid (GABA) receptors, which co-colonize with µ-opioid receptors and mediate CSA. The pattern of ataxic breathing associated with these medications is like that induced by opioids on polysomnogram. Finally, ticagrelor also causes periodic breathing and CSA by increasing central chemosensitivity and ventilatory response to carbon dioxide. Given the potential consequences of CSA and the association between some of these medications with mortality, it is critical to recognize these adverse drug reactions, particularly because discontinuation of the offending agents has been shown to eliminate CSA.

Feasibility of oropharyngeal and respiratory muscle training in individuals with OSA and spinal cord injury or disease: A pilot study.

OBJECTIVES: To examine the feasibility of individuals with spinal cord injury or disease (SCI/D) to perform combined oropharyngeal and respiratory muscle training (RMT) and determine its impact on their respiratory function. METHODS: A prospective study at a single Veterans Affairs (VA) Medical Center. Inclusion criteria included: 1) Veterans with chronic SCI/D (>6 months postinjury and American Spinal Injury Association (ASIA) classification A-D) and 2) evidence of OSA by apnea-hypopnea index (AHI ≥5 events/h). Eligible participants were randomly assigned to either an experimental (exercise) group that involved performing daily inspiratory, expiratory (using POWERbreathe and Expiratory Muscle Strength Trainer 150 devices, respectively), and tongue strengthening exercises or a control (sham) group that involved using a sham device, for a 3-month period. Spirometry, maximal expiratory pressure (MEP), maximal inspiratory pressure (MIP), polysomnography, and sleep questionnaires were assessed at baseline and at 3 months. RESULTS: Twenty-four individuals were randomized (12 participants in each arm). A total of eight (67%) participants completed the exercise arm, and ten (83%) participants completed the sham arm. MIP was significantly increased (p < 0.05) in the exercise group compared with the baseline. CONCLUSIONS: Combined oropharyngeal and RMT are feasible for individuals with SCI/D. Future studies are needed to determine the clinical efficacy of these respiratory muscle exercises.

Nitrogen and spent coffee ground for enhancing nutritional, morphological, flowering and antioxidant properties of Chrysanthemum (Chrysanthemum morfolium Ramat).

Chrysanthemum is one of the most attractive flowering plants widely grown commercially worldwide. Having a good source of organic fertilizers plays an important role in meeting the increasing demand for these plants, which requires high-quality flowers and a high survival time for the longest period. The effect of nitrogen (N) coupled with spent coffee ground (SCG) at various levels (0.0, 2.5, 5.0, 7.5, 10.0°% w/w) was evaluated on growth performance and chemical components of the Chrysanthemum over two years in a pot scale. Overall, total dry matter (TDM) was significantly enhanced with N+ by 125 and 97°% over N- in the first and second years, respectively. SCG also enhanced TDM up to the highest level of application in the range of 27-98°% and 18-81°% over SCG (0.0°%) in the same years, respectively. The interaction effect between N and SCG was perfect on TDM, flower number, and flower dry weight. Similarly, total antioxidant activities when N and SCG were coupled together gave respective increments ranging from 11.8 to 45.9 U/g DW and from 2.1 to 15.9 U/g DW compared to N alone (5.8 and 0.9 U/g DW) in both leaves and flowers, respectively. Extracts of plant treated with N and 10°% SCG exhibited a higher content of rosmarinic, caffeic, chlorogenic, vanillic acids, and rutin in the leaves. SCG as a natural organic source is easy to obtain and is a practical and cost-effective solution to plant nutrition, which can be valuable for ornamental plants, especially when combined with nitrogen.

Magneto-convection of nanofluid flow over multiple rotating cylinders in a confined space with elastic walls and ventilated ports.

In this study, convective heat transfer for nanofluid flow over multiple rotating cylinder in a confined space is analyzed under magnetic field while enclosure has one inlet and one outlet port. Three identical circular cylinder are used and the two walls of the cavity are considered to be elastic. The coupled fluid-structure interaction and magneto-convection problem is solved by finite element method. Impacts of rotational Reynolds number (Rew between -100 and 100), Hartmann number (Ha between 0 and 50), cylinder size (R between 0.001H and 0.11H) and Cauchy number (Ca between 10-8 and 10-3) on the flow and thermal performance features are explored. The flow field and recirculation inside the cavity are significantly affected by the activation of rotation and magnetic field. The vortices are suppressed by increasing the strength of magnetic field and thermal performance is improved. Thermal performance of 56.6% is achieved by activation of magnetic field at the highest strength with rotations of the circular cylinders. When rotations are active, heat transfer rate is reduced while up to 40% reduction is obtained without magnetic field. Cylinder size has the highest impact on the overall thermal performance improvement while up to 132% enhancements are achieved. The contribution of elastic walls on the thermal performance is slight while less than 5% improvements in the average heat transfer is obtained. An optimization study leads to 12.7% higher thermal performance improvements as compared to best case of parametric computational fluid dynamics simulation results while the optimum values of (Rew, Ha, R) is obtained as (-80.66, 50, 0.11H).

Intensive support does not improve positive-airway pressure use in spinal cord injury/disease: a randomized clinical trial.

STUDY OBJECTIVE: Treatment of sleep-disordered breathing (SDB) with positive airway pressure (PAP) therapy has unique clinical challenges in individuals living with spinal cord injuries and diseases (spinal cord injury [SCI]/D). Interventions focused on increasing PAP use have not been studied in this population. We aimed to evaluate the benefits of a program to increase PAP use among Veterans with SCI/D and SDB. METHODS: Randomized controlled trial comparing a behavioral Intervention (n = 32) and educational control (n = 31), both including one face-to-face and five telephone sessions over 3 months. The intervention included education about SDB and PAP, goal setting, troubleshooting, and motivational enhancement. The control arm included non-directive sleep education only. RESULTS: Primary outcomes were objective PAP use (nights ≥4 hours used within 90 days) and sleep quality (Pittsburgh Sleep Quality Index [PSQI] at 3 months). These did not differ between intervention and control (main outcome timepoint; mean difference 3.5 [-9.0, 15.9] nights/week for PAP use; p = .578; -1.1 [-2.8, 0.6] points for PSQI; p = .219). Secondary outcomes included fatigue, depression, function, and quality of life. Only fatigue improved significantly more in the intervention versus the control group (p = .025). Across groups, more PAP use was associated with larger improvements in sleep quality, insomnia, sleepiness, fatigue, and depression at some time points. CONCLUSIONS: PAP use in Veterans with SCI/D and SDB is low, and a 3-month supportive/behavioral program did not show significant benefit compared to education alone. Overall, more PAP use was associated with improved symptoms suggesting more intensive support, such as in-home assistance, may be required to increase PAP use in these patients. CLINICAL TRIALS INFORMATION: Title: "Treatment of Sleep Disordered Breathing in Patients with SCI." Registration number: NCT02830074. Website: https://clinicaltrials.gov/study/NCT02830074?cond=Sleep%20Apnea&term=badr&rank=5.

The Clinical Relevance of Autonomic Dysfunction, Cerebral Hemodynamics, and Sleep Interactions in Individuals Living With SCI.

A myriad of physiological impairments is seen in individuals after a spinal cord injury (SCI). These include altered autonomic function, cerebral hemodynamics, and sleep. These physiological systems are interconnected and likely insidiously interact leading to secondary complications. These impairments negatively influence quality of life. A comprehensive review of these systems, and their interplay, may improve clinical treatment and the rehabilitation plan of individuals living with SCI. Thus, these physiological measures should receive more clinical consideration. This special communication introduces the under investigated autonomic dysfunction, cerebral hemodynamics, and sleep disorders in people with SCI to stakeholders involved in SCI rehabilitation. We also discuss the linkage between autonomic dysfunction, cerebral hemodynamics, and sleep disorders and some secondary outcomes are discussed. Recent evidence is synthesized to make clinical recommendations on the assessment and potential management of important autonomic, cerebral hemodynamics, and sleep-related dysfunction in people with SCI. Finally, a few recommendations for clinicians and researchers are provided.

Electrospinning of photochromic poly(ethylene terephthalate) nanofibers toward information authentication.

The use of photochromism to enhance the anti-counterfeiting of a wide range of economic goods is an intriguing prospect. Creating a translucent anti-counterfeiting nanocomposite is critical to improving the engineering procedures of the encoding materials. Herein, we use electrospinning to produce anti-counterfeiting nanofibrous films from nanoparticles of rare-earth aluminate (NREA) and recycled poly(ethylene terephthalate) (PET). Different nanofiber films with distinct emission properties were created using different ratios of NREA. The ultraviolet (UV)-induced photochromism of the NREA@PET nanofibers was proved. Immobilizing NREA at the nanoscale ensures better dispersion without agglomeration in the PET nanofibrous matrix, which is essential for the development of transparent NREA@PET films. Diameters of 4-13 nm for NREA were shown using transmission electron microscopy. X-ray fluorescence spectroscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, elemental mapping, and other techniques were used to investigate the photochromic nanofibers' morphology, elemental contents, optical transmittance, and mechanical performance. It was observed that the nanofiber diameter in NREA@PET was between 150 and 250 nm. Excitation and emission bands of electrospun NREA@PET nanofibrous films were monitored at 365 and 518 nm, respectively. The superhydrophobicity of NREA@PET increased with increasing NREA concentration. The transparent nanofibers exhibited fast and reversible dual-mode fluorescent photochromism to green emission without fatigue when stimulated beneath a UV source. Using the present anti-counterfeiting films can be regarded as a simple technique to develop flexible materials to launch an ideal marketplace with affordable societal and economic advantages.

Establishment and inactivation of mono-species biofilm in a semipilot-scale water distribution system using nanocomposite of silver nanoparticles/montmorillonite loaded cationic chitosan.

This study presents a novel approach in the synthesis and characterization of nanocomposites comprising cationic chitosan (CCS) blended with varying concentrations of silver nanoparticles/montmorillonite (AgNPs/MMT). AgNPs/MMT was synthesized using soluble starch as a reducing and stabilizing agent. Subsequently, nanocomposites, namely CCS/AgMMT-0, CCS/AgMMT-0.5, CCS/AgMMT-1.5, and CCS/AgMMT-2.5, were developed by blending 2.5 g of CCS with 0, 0.5, 1.5, and 2.5 g of AgNPs/MMT, respectively, and the corresponding nanocomposites were prepared using ball milling technique. Transmission electron microscopy (TEM) analysis revealed the formation of nanocomposites that exhibiting nearly spherical morphologies. Dynamic light scattering (DLS) measurements displayed average particle sizes of 1183 nm, 131 nm, 140 nm, and 188 nm for CCS/AgMMT-0, CCS/AgMMT-0.5, CCS/AgMMT-1.5, and CCS/AgMMT-2.5, respectively. The narrow polydispersity index (~0.5) indicated uniform particle size distributions across the nanocomposites, affirming monodispersity. Moreover, the zeta potential values exceeding 30 mV across all nanocomposites that confirmed their stability against agglomeration. Notably, CCS/AgMMT-2.5 nanocomposite exhibited potent antibacterial and antibiofilm properties against diverse pipeline materials. Findings showed that after 15 days of incubation, the highest populations of biofilm cells, Pseudomonas aeruginosa biofilm, developed over UPVC, MDPE, DCI, and SS, with corresponding HPCs of 4.79, 6.38, 8.81, and 7.24 CFU/cm2. The highest cell densities of Enterococcus faecalis biofilm in the identical situation were 4.19, 5.89, 8.12, and 6.9 CFU/cm2. The nanocomposite CCS/AgMMT-2.5 exhibited the largest measured zone of inhibition (ZOI) against both P. aeruginosa and E. faecalis, with measured ZOI values of 19 ± 0.65 and 17 ± 0.21 mm, respectively. Remarkably, the research indicates that the youngest biofilm exhibited the most notable rate of inactivation when exposed to a dose of 150 mg/L, in comparison to the mature biofilm. These such informative findings could offer valuable insights into the development of effective antibiofilm agents and materials applicable in diverse sectors such as water treatment facilities, medical devices, and industrial pipelines.

Enhanced Adsorption of Textile Dyes by a Novel Sulfonated Activated Carbon Derived from Pomegranate Peel Waste: Isotherm, Kinetic and Thermodynamic Study.

The rapid growth of the dye and textile industry has raised significant public concerns regarding the pollution caused by dye wastewater, which poses potential risks to human health. In this study, we successfully improved the adsorption efficiency of activated carbon derived from pomegranate peel waste (PPAC) through a single-step and surface modification approach using 5-sulfonate-salicylaldehyde sodium salt. This innovative and effective sulfonation approach to produce sulfonated activated carbon (S-PPAC) proved to be highly effective in removing crystal violet dye (CV) from polluted water. The prepared PPAC and S-PPAC were characterized via FESEM, EDS, FTIR and BET surface area. Characterization studies confirmed the highly porous structure of the PPAC and its successful surface modification, with surface areas reaching 1180.63 m2/g and 740.75 m2/g for the PPAC and S-PPAC, respectively. The maximum adsorption capacity was achieved at 785.53 mg/g with the S-PPAC, an increase of 22.76% compared to the PPAC at 45 °C. The isothermic adsorption and kinetic studies demonstrated that the adsorption process aligned well with the Freundlich isotherm model and followed the Elovich kinetic model, respectively. The thermodynamic study confirmed that the adsorption of CV dye was endothermic, spontaneous and thermodynamically favorable onto PPAC and S-PPAC.

Activated Carbon-Incorporated Tragacanth Gum Hydrogel Biocomposite: A Promising Adsorbent for Crystal Violet Dye Removal from Aqueous Solutions.

Biomaterials-based adsorbents have emerged as a sustainable and promising solution for water purification, owing to their eco-friendly nature and remarkable adsorption capacities. In this study, a biocomposite hydrogel was prepared by the incorporation of activated carbon derived from pomegranate peels (PPAC) in tragacanth gum (TG). The hydrogel biocomposite (PPAC/TG) showed a porous structure, a negative surface charge at a pH of more than 4.9, and good stability in aqueous media. The adsorption properties of the PPAC/TG hydrogel biocomposite were assessed for the removal of crystal violet dye (CV) from aqueous solutions using a batch adsorption. The equilibrium adsorption data followed the Sips isotherm model, as supported by the calculated R2 (>0.99), r-χ2 (<64), and standard error values (<16). According to the Sips model, the maximum values of the adsorption capacity of PPAC/TG were 455.61, 470.86, and 477.37 mg/g at temperatures of 25, 30, and 35 °C, respectively. The adsorption kinetic of CV onto the PPAC/TG hydrogel biocomposite was well described by the pseudo-second-order model with R2 values more than 0.999 and r-χ2 values less than 12. Thermodynamic studies confirmed that the CV dye adsorption was spontaneous and endothermic. Furthermore, the prepared hydrogel exhibited excellent reusability, retaining its adsorption capacity even after being used more than five times. Overall, this study concludes that the prepared PPAC/TG exhibited a significant adsorption capacity for cationic dyes, indicating its potential as an effective and eco-friendly adsorbent for water treatment.