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1.
Int J Biol Macromol ; 273(Pt 2): 132815, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38825279

ABSTRACT

Modern environmental organic chemistry is focused on developing cost-efficient, versatile, environmentally acceptable catalytic chemicals that are also highly effective. Herein, hybrid calcium-chitosan nanocomposite films was prepared by doping calcium oxide molecules into a chitosan matrix at weight percentage (15, 20, and 25 % wt. chitosan­calcium) using an easy and affordable simple co-precipitation process. The CS-CaO nanocomposite's structure was elucidated using analytical techniques such as Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Based on the X ray diffraction (XRD) measurements, the crystallinity was reduced by the incorporation of the CaO molecules. Also, from the calculation of the Debye-Scherrer equation on this X-ray diffraction (XRD) pattern, the crystallite size was found to be 17.2 nm for the nanocomposite film with 20 % wt. The energy dispersive spectroscopy graph demonstrated the presence of the distinctive Ca element signals within the chitosan, with the amount in a sample of 20 % wt. being discovered to be 21.32 % wt. For the synthesis of bis-hydrazono[1,2,4]thiadiazoles, the obtained CS-CaO nanocomposite could be employed as a potent heterogeneous recyclable catalyst. Better reaction yields, quicker reactions, softer reaction conditions, and green reusable efficient biocatalysts for several uses are just a few advantages of this approach.


Subject(s)
Calcium Compounds , Chitosan , Green Chemistry Technology , Nanocomposites , Oxides , Chitosan/chemistry , Nanocomposites/chemistry , Calcium Compounds/chemistry , Oxides/chemistry , Thiadiazoles/chemistry , X-Ray Diffraction , Spectroscopy, Fourier Transform Infrared , Catalysis
2.
PLoS One ; 19(6): e0302135, 2024.
Article in English | MEDLINE | ID: mdl-38861530

ABSTRACT

Soilless agriculture is acknowledged worldwide because it uses organic leftovers as a means of supporting intensive and efficient plant production. However, the quality of potting media deteriorates because of lower nutrient content and excessive shrinkage of most organic materials. A current study was undertaken to identify the optimal blend of locally available organic materials with desirable qualities for use as potting media. Therefore, different ingredients, viz., Pinus roxburghii needles, sugarcane bagasse, and farmyard manure were used alone or in combination as potting media to test their suitability by growing spinach as a test crop. Results showed that an increase in Pinus roxburghii needles and sugarcane bagasse decreased medium pH and electrical conductivity. Higher pH and electrical conductivity were recorded for the treatments having a higher farmyard manure ratio (≥50%) in combination. Except for pine needles 100%, pH and electrical conductivity were in the recommended range. The growth attributes include, leaves plant-1, shoot length, fresh- and dry shoot weight along with plant macronutrients (nitrogen, phosphorous, and potassium) and micronutrients (iron, copper, manganese, and zinc) content were higher in treatment pine needles 50%+farmyard manure 50% followed by pine needles 25%+farmyard manure 50%+sugarcane bagasse 25%. Moreover, the particular treatment of pine needles 50%+farmyard manure 50% exhibited the highest concentrations of macro- (nitrogen, phosphorus, and potassium) as well as micronutrients (iron, copper, manganese, and zinc) in the potting media following the harvest. This study highlights the potential of utilizing agro-industrial litter/waste as a soilless growing medium for spinach production under greenhouse conditions. When employed in appropriate proportions, this approach not only addresses disposal concerns but also proves effective for sustainable cultivation. Further research is needed to investigate the use of these wastes as potting media by mixing various particle-size ingredients.


Subject(s)
Manure , Pinus , Saccharum , Manure/analysis , Saccharum/growth & development , Saccharum/chemistry , Pinus/growth & development , Cellulose , Vegetables/growth & development , Vegetables/chemistry , Spinacia oleracea/growth & development , Spinacia oleracea/metabolism , Hydrogen-Ion Concentration , Electric Conductivity , Agriculture/methods , Plant Leaves/growth & development , Plant Leaves/chemistry , Soil/chemistry , Nitrogen/analysis
3.
Int J Biol Macromol ; 269(Pt 2): 131935, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38723542

ABSTRACT

Nanocomposites, blending the unique properties of inorganic nanoparticles with polymers, are gaining momentum in various industries. This study delves into the synthesis and characterization of barium oxide (BaO)-doped carboxymethyl cellulose (CMC) nanocomposites, focusing on their structural, optical, electrical, and dielectric properties. Using an in-situ polymerization method, CMC films were doped with 5 % and 10 % BaO nanoparticles. X-ray diffraction analysis revealed that the doped samples exhibited enhanced crystallinity compared to pure CMC, with crystallinity percentages measured at 37.95 % and 28.86 % for 5 % and 10 % BaO, respectively, indicating the successful incorporation of BaO. Scanning electron microscopy illustrated the distribution of BaO nanoparticles, showing spherical agglomerations on the film surface. SEM analysis reveals emergence of spherical agglomerations and bright spots on nanocomposite film surface upon BaO introduction, indicating BaO nanoparticles presence. Further, the BaO nanoparticles act as catalytic and nucleating agents, influencing crystalline structure nucleation and growth, potentially enhancing film homogeneity and structural integrity. In addition, UV-visible spectroscopy elucidated the optical properties, indicating a shift in the bandgap from indirect to direct with BaO addition. The bandgap values decrease upon the addition of BaO, indicating a transition from an amorphous to a nanocrystalline structure, with respective reduction percentages of 22.73 % and 10.71 % for the 5%BaO/CMC and 10 %BaO/CMC samples compared to CMC. Electrical conductivity measurements showed enhanced conductivity in 10 % BaO/CMC due to improved charge carrier mobility, supported by dielectric studies demonstrating increased dielectric. The introduction of 5 % and 10 % BaO resulted in reductions of approximately 62.06 % and 65.77 %, respectively, compared to the pure CMC sample. This decrease in dielectric loss indicates an enhancement in the electrical properties of the nanocomposites. This comprehensive investigation could give further insights into the different properties of BaO-doped CMC nanocomposites, offering insights into their potential applications in various fields such as electronics, energy storage, and optoelectronics.


Subject(s)
Carboxymethylcellulose Sodium , Nanocomposites , Nanocomposites/chemistry , Carboxymethylcellulose Sodium/chemistry , Barium Compounds/chemistry , X-Ray Diffraction , Electric Conductivity
4.
Sci Total Environ ; 928: 172265, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38621534

ABSTRACT

Extensive unforested sandy areas on the margins of floodplains and riverbeds, formed by dunes, barchans, and accumulation berms, are a ubiquitous feature across northern Eurasia and Alaska. These dynamic landscapes, which bear witness to the complex Holocene and modern climatic fluctuations, provide a unique opportunity to study ecosystem evolution. Within this heterogeneous assemblage, active dunes, characterized by their very sparse plant communities, contrast sharply with the surrounding taiga (boreal) forests common for the stabilized dunes. This juxtaposition makes these regions to natural laboratories to study vegetation succession and soil development. Through a comprehensive analysis of climate, geomorphology, vegetation, soil properties, and microbiome composition, we elucidate the intricacies of cyclic and linear ecosystem evolution within a representative sandy area located along the lower Nadym River in Siberia, approximately 100 km south of the Arctic Circle. The shift in the Holocene wind regime and the slow development of vegetation under harsh climatic conditions promoted cyclical ecosystem dynamics that precluded the attainment of a steady state. This cyclical trajectory is exemplified by Arenosols, characterized by extremely sparse vegetation and undifferentiated horizons. Conversely, accelerated vegetation growth within wind-protected enclaves on marginally stabilized soils facilitated sand stabilization and subsequent pedogenesis towards Podzols. Based on soil acidification due to litter input (mainly needles, lichens, and mosses) and the succession of microbial communities, we investigated constraints on carbon and nutrient availability during the initial stages of pedogenesis. In summary, the comprehensive study of initial ecosystem development on sand dunes within taiga forests has facilitated the elucidation of both common phases and spatiotemporal dynamics of vegetation and soil succession. This analysis has further clarified the existence of both cyclic and linear trajectories within the successional processes of ecosystem evolution.


Subject(s)
Ecosystem , Soil , Taiga , Siberia , Soil/chemistry , Sand , Environmental Monitoring , Microbiota , Soil Microbiology
5.
Int J Biol Macromol ; 264(Pt 1): 129990, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38360246

ABSTRACT

In this study, a single step in situ sol-gel method was used to syntheses nanocomposite films using chitosan (CS) as the basis material, with the addition of silver oxide nanoparticles (Ag2O) at several weight percentages (5 %, 10 %, and 15 % Ag2O/CS). The structural characteristics of Ag2O/CS films were investigated using a range of analytical techniques. The presence of the primary distinctive peaks of chitosan was verified using FTIR spectra analysis. However, a minor displacement was observed in these peaks due to the chemical interaction occurring with silver oxide molecules. XRD analysis demonstrated a significant increase in the crystallinity of chitosan when it interacted with metal oxide nanoparticles. Furthermore, it is believed that the interaction between silver oxide and the active binding sites of chitosan is responsible for the evenly dispersed clusters shown in the micrographs of the chitosan surface, as well as the random aggregations within the pores. EDS technique successfully identified the presence of distinctive silver signals within the nanocomposite material, indicating the successful absorption of silver into the surface of the polymer. The developed Ag2O/CS nanocomposite showed promising antibacterial activity against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Bacillus subtilis, Enterococcus faecalis and Staphylococcus aureus). Also, Ag2O/CS nanocomposite exhibited marked antifungal activity against Candida albicans, Aspergillus flavus, A. fumigatus, A. niger, and Penicillium chrysogenum. The antioxidant activity of the developed nanocomposite films was studied by ABTS radical scavenging. The highest antioxidant and antibacterial properties were achieved by including 15 % silver oxide into the chitosan. Therefore, our finding indicate that chitosan­silver oxide nanocomposites exhibits significant potential as a viable material for application in several sectors of the food packaging industry.


Subject(s)
Anti-Infective Agents , Chitosan , Metal Nanoparticles , Nanocomposites , Oxides , Silver Compounds , Chitosan/chemistry , Antioxidants/pharmacology , Food Packaging , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Metal Nanoparticles/chemistry , Nanocomposites/chemistry
6.
Angiology ; : 33197241226863, 2024 Jan 07.
Article in English | MEDLINE | ID: mdl-38185884

ABSTRACT

Female gender is a risk factor in several cardiac surgery risk stratification systems. This study explored the differences in the outcomes following triple heart valve surgery in men vs women. The study included 250 patients (males n = 101; females n = 149) who underwent triple valve surgery from 2009 to 2020. BMI (body mass index) was higher in females (29.6 vs 26.5 kg/m2, P < .001), and diabetes was more common in males (44 vs 42%, P = .012). The ejection fraction was higher in females (55 vs 50%, P < .001). The severity of mitral valve stenosis and tricuspid valve regurgitation was significantly greater in females (33.11 vs 27.72%, P = .003 and 44.30 vs 19.8%, P < .001, respectively). Mitral valve replacement was more common in females (P < .001), and they had lower concomitant coronary artery bypass grafting (P = .001). Bleeding and renal failure were lower in females (P = .021 and <0.001, respectively). Hospital mortality, readmission, and reintervention were not significantly different between genders. By multivariable analysis, male gender was a risk factor for lower survival [HR (hazard ratio): 2.18; P = .024]. Triple valve surgery can be performed safely in both genders, with better long-term survival in females. Female gender was not a risk factor in patients undergoing triple valve surgery.

7.
Sci Rep ; 13(1): 19064, 2023 Nov 04.
Article in English | MEDLINE | ID: mdl-37925477

ABSTRACT

Date palm stones are regarded as possible alternatives to activated carbon (AC) precursors with high potential for various environmental applications. In this research study, date palm stones derived activated carbon (DPSAC) was used as adsorbent for removing toxic remazol brilliant blue R (RBBR). The synthesis of DPSAC involved a chemical treatment using KOH and NaOH (1:1). Characterization of DPSAC revealed that it exhibited a BET surface area of 715.30 m2/g, Langmuir surface area of 1061.93 m2/g, total pore volume of 0.39 cm3/g, and average pore diameter of 2.15 nm. Adsorption uptake of RBBR increased (from 24.54 to 248.54 mg/g), whereas the removal percentage decreased (from 98.16 to 82.85%) when the initial RBBR concentration increased (from 25 to 300 mg/L). The adsorption process performed best under acidic conditions (pH 3), with an RBBR uptake of 98.33 mg/g. Because of the high R2 values (0.9906 and 0.9779) and low average errors (6.24 and 13.95%), this adsorption process followed the Freundlich isotherm and pseudo-first-order (PFO) models, respectively. The Langmuir adsorption capacity (Qm) was 319.63 mg/g. Thermodynamic parameters were - 11.34 kJ/mol for ∆H° (exothermic in nature), 0.05 kJ/mol K for ∆S° (increasing randomness level at solid-liquid interface), - 27.37 kJ/mol for ∆G° (spontaneous), and 6.84 kJ/mol for Ea (controlled by physisorption).

8.
Polymers (Basel) ; 15(20)2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37896376

ABSTRACT

Polymeric films made from chitosan (CS) doped with metal oxide (MO = cobalt (II) oxide and strontium oxide) nanoparticles at different concentrations (5, 10, 15, and 20% wt. MO/CS) were fabricated with the solution cast method. FTIR, SEM, and XRD spectra were used to study the structural features of those nanocomposite films. The FTIR spectra of chitosan showed the main characteristic peaks that are usually present, but they were shifted considerably by the chemical interaction with metal oxides. FTIR analysis of the hybrid chitosan-CoO nanocomposite exhibited notable peaks at 558 and 681 cm-1. Conversely, the FTIR analysis of the chitosan-SrO composite displayed peaks at 733.23 cm-1, 810.10 cm-1, and 856.39 cm-1, which can be attributed to the bending vibrations of Co-O and Sr-O bonds, respectively. In addition, the SEM graphs showed a noticeable morphological change on the surface of chitosan, which may be due to surface adsorption with metal oxide nanoparticles. The XRD pattern also revealed a clear change in the crystallinity of chitosan when it is in contact with metal oxide nanoparticles. The presence of characteristic signals for cobalt (Co) and strontium (Sr) are clearly shown in the EDX examinations, providing convincing evidence for their incorporation into the chitosan matrix. Moreover, the stability of the nanoparticle-chitosan coordinated bonding was verified from the accurate and broadly parametrized semi-empirical tight-binding quantum chemistry calculation. This leads to the determination of the structures' chemical hardness as estimated from the frontier's orbital calculations. We characterized the dielectric properties in terms of the real and imaginary dielectric permittivity as a function of frequency. Dielectric findings reveal the existence of extensive interactions of CoO and SrO, more pronounced for SrO, with the functional groups of CS through coordination bonding. This induces the charge transfer of the complexes between CoO and SrO and the CS chains and a decrease in the amount of the crystalline phase, as verified from the XRD patterns.

9.
Int J Biol Macromol ; 253(Pt 4): 126856, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37714231

ABSTRACT

This research aimed to prepare, characterize, and investigate the biological efficacy of chitosan­cobalt (II) oxide hybrid nanocomposites against a variety of micrograms. Analytical methods, FTIR, SEM, XRD, and EDX, were utilized to thoroughly characterize the produced CS-CoO nanocomposite. In FTIR spectra, the presence of the chitosan peaks in addition to that of CoO at 681 and 558 cm-1 confirmed that CoO molecules interact with the chitosan backbone. Moreover, in the XRD measurements, significantly less chitosan crystallinity was observed. Due to the incorporation of a larger amount of cobalt oxide within the polymer matrix. Applying the Debye-Sherrer calculation, the crystallite size was obviously reduced from 48.24 nm (5 wt %) to 19.27 nm (20 wt %) for the obtained nanocomposites. Furthermore, SEM measurements showed a transformation in the chitosan surface with the physical adsorption of CoO molecules on the surface active sites of chitosan that were visible in SEM graphs. Additionally, EDX determined the amount of Co element within the chitosan, with the sample of 20 wt % weight being found to be 19.26 wt %. The variable dose well-diffusion method was utilized to assess the efficacy of the CS-Co nanocomposite against a wide range of bacteria and fungi. CS - CoO nanocomposite is more effective than chitosan alone as an antibacterial agent against both Gram-positive and Gram-negative bacteria. Moreover, the MTT approach was employed to measure the cytotoxicity based on the cell viability of different cancer cell lines under different UV expositions. The proportion of the destroyed cells elevated due to the easy diffusion of CS - CoO nanocomposite into cancer cells as UV-free anticancer activity. UV exposition has stimulated the anticancer activity, which was attributed to an increase in ROS generation caused by the increased dose of the chitosan and its CS - CoO nanocomposites. Furthermore, the antioxidant capacities of the prepared nano-composites thin films were validated using the DPPH free radical scavenging method and showed good antioxidant activities with the DPPH radical compared with standard vitamin C. It has been noticed that by increasing the content of CoO nanoparticles from 5 to 20 wt %, the biological activity of the prepared nanocomposites was enhanced.


Subject(s)
Chitosan , Nanocomposites , Chitosan/pharmacology , Chitosan/chemistry , Anti-Bacterial Agents/chemistry , Antioxidants , Gram-Negative Bacteria , Gram-Positive Bacteria , Oxides/pharmacology , Cobalt , Nanocomposites/chemistry , Pharmaceutical Preparations
10.
Polymers (Basel) ; 15(18)2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37765671

ABSTRACT

The diverse applications of metal oxide-biopolymer matrix as a nanocomposite heterogenous catalyst have caused many researches to scrutinize the potential of this framework. In this study, a novel hybrid barium oxide-chitosan nanocomposite was synthesized through a facile and cost-effective co-precipitation method by doping barium oxide nanoparticles within the chitosan matrix at a weight percentage of 20 wt.% BaO-chitosan. A thin film of the novel hybrid material was produced by casting the nanocomposite solution in a petri dish. Several instrumental methods, including Fourier-transform infrared (FTIR), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), were used to analyze and characterize the structure of the BaO-CS nanocomposite. The chemical interaction with barium oxide molecules resulted in a noticeable displacement of the most significant chitosan-specific peaks in the FTIR spectra. When the surface morphology of SEM graphs was analyzed, a dramatic morphological change in the chitosan surface was also discovered; this morphological change can be attributed to the surface adsorption of BaO molecules. Additionally, the patterns of the XRD demonstrated that the crystallinity of the material, chitosan, appears to be enhanced upon interaction with barium oxide molecules with the active sites, OH and NH2 groups, along the chitosan backbone. The prepared BaO-CS nanocomposite can be used successfully as an effective heterogenous recyclable catalyst for the reaction of N,N'-(alkane-diyl)bis(2-chloroacetamide) with 2-(arylidinehydrazine)-1-carbothioamide as a novel synthetic approach to prepare 2-hydrazonothiazol-4(5H)-ones. This new method provides a number of benefits, including quick and permissive reaction conditions, better reaction yields, and sustainable catalysts for multiple uses.

11.
Int J Artif Organs ; 46(6): 384-389, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37125784

ABSTRACT

We aimed to compare the outcomes of ECMO with and without IABP for postcardiotomy cardiogenic shock. The study included 103 patients who needed ECMO for postcardiotomy cardiogenic shock. Patients were grouped according to the use of IABP into ECMO without IABP (n = 43) and ECMO with IABP (n = 60). The study endpoints were hospital complications, successful weaning, and survival. Patients with IABP had lower preoperative ejection fraction (p = 0.002). There was no difference in stroke (p = 0.97), limb ischemic (p = 0.32), and duration of ICU stay (p = 0.11) between groups. Successful weaning was non-significantly higher with IABP (36 (60%) vs 19 (44.19%); p = 0.11). Predictors of successful weaning were inversely related to the high pre-ECMO lactate levels (OR: 0.89; p = 0.01), active endocarditis (OR: 0.06; p = 0.02), older age (OR: 0.95; p = 0.02), and aortic valve replacement (OR: 0.26; p = 0.04). There was no difference in survival between groups (p = 0.80). Our study did not support the routine use of IABP during ECMO support.


Subject(s)
Extracorporeal Membrane Oxygenation , Heart-Assist Devices , Humans , Shock, Cardiogenic/etiology , Shock, Cardiogenic/therapy , Extracorporeal Membrane Oxygenation/adverse effects , Intra-Aortic Balloon Pumping/adverse effects , Heart-Assist Devices/adverse effects , Aortic Valve , Retrospective Studies
12.
Quant Imaging Med Surg ; 13(4): 2507-2513, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37064355

ABSTRACT

Background: Stroke is one of the most feared complications post coronary artery bypass with aortic calcifications being the commonest source of embolic stroke. The aim of our study was to determine the clinical impact and usefulness of routine use of plain chest computerised tomography to screen for aortic calcification on incidence of postoperative stroke in coronary artery bypass grafting (CABG) patients. Methods: This is a retrospective case-control study that included four hundred and five patients who underwent primary isolated CABG and had preoperative plain chest computerised tomography as a screening for aortic calcification. Aortic calcification was classified according to the area involved (ascending, arch, arch vessels and descending aorta) and the pattern of calcification. Patients were divided into two groups according to the incidence of postoperative stroke and the aortic calcification distribution was compared between the two groups. Stroke predictors were studies using univariate and multivariate regression analysis. Results: Fourteen patients (3.5%) developed postoperative stroke. There was no difference in preoperative and operative characteristics between patients who developed postoperative stroke and those who did not, except for the history of preoperative stroke or transient ischemic attack (TIA) that was higher in the group who developed postoperative stroke (50.00% vs. 6.19%, P<0.001). Patients who developed postoperative stroke had higher percentage of aortic root calcification (78.57% vs. 64.18%), ascending aortic calcification (28.57% vs. 19.07%) and descending aortic calcification (85.71% vs. 73.71%) but none of them reached statistical significance. History of preoperative stroke or TIA was the only significant predictor of postoperative stroke using both univariate and multivariate regression models. Conclusions: Our study showed the importance of preoperative computed tomography (CT) scan of the chest as a screening tool as it detected a high prevalence of aortic calcification in our patients. However, its impact on prevention of postoperative stroke needs to be investigated further in future prospective studies.

14.
Toxics ; 11(2)2023 Jan 19.
Article in English | MEDLINE | ID: mdl-36850971

ABSTRACT

Biochar's agricultural and environmental benefits have been widely demonstrated; however, it may cause environmental contamination if it contains large amounts of pollutants such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs). Therefore, this study aimed to assess the contents of PAHs and HM in a range of biochars generated from different sources and pyrolysis temperatures. A range of feedstock was converted to biochar, including sewage sludge (SS), olive mill pomace (OP), feather meal (FM), soft offal meal (CSM), chicken manure (CM), and date palm residues (DPR). Each feedstock was then pyrolyzed at three temperatures of 300, 500, or 700 °C, thereby producing a total of 18 types of biochar. These biochar products were analyzed for 16 PAHs and eight metals (Cr, Mn, Fe, Ni, Cu, Zn, Cd, and Pb). Benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo(a)pyrene were significantly greater in the biochar produced at 700 °C than in that produced at 300 °C, especially for CM. The concentrations of dibenz(a,h)anthracene were significantly lower at 700 °C but greater at 500 °C and 300 °C in DPR. Increasing the pyrolysis temperature from 300 to 700 °C significantly increased the concentrations of metals, including Cr in SS and OP; Mn in CM; and Fe, Ni, Cu, and Zn in SS. However, the concentration of Cd was significantly lower in the SS when biochar was produced at 700 °C than at 500 or 300 °C. The type of feedstock used and the pyrolysis temperature are key factors influencing the contents of PAHs and HMs in biochar, both of which need to be considered during the production and use of biochar. Further investigations are recommended to establish the relationships between pyrolysis temperature and types of feedstock and the formation of PAH or the concentrations of metals. Monitoring the concentrations of PAHs and HMs before applying biochar to soil is also recommended.

15.
Rev. bras. cir. cardiovasc ; 38(1): 52-61, Jan.-Feb. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1423075

ABSTRACT

ABSTRACT Introduction: Repeat transcatheter mitral valve replacement (rTMVR) has emerged as a new option for the management of high-risk patients unsuitable for repeat surgical mitral valve replacement (rSMVR). The aim of this study was to compare hospital outcomes, survival, and reoperations after rTMVR versus surgical mitral valve replacement. Methods: We compared patients who underwent rTMVR (n=22) from 2017 to 2019 (Group 1) to patients who underwent rSMVR (n=98) with or without tricuspid valve surgery from 2009 to 2019 (Group 2). We excluded patients who underwent a concomitant transcatheter aortic valve replacement or other concomitant surgery. Results: Patients in Group 1 were significantly older (72.5 [67-78] vs. 57 [52-64] years, P<0.001). There was no diference in EuroSCORE II between groups (6.56 [5.47-8.04] vs. 6.74 [4.28-11.84], P=0.86). Implanted valve size was 26 (26-29) mm in Group 1 and 25 (25-27) mm in Group 2 (P=0.106). There was no diference in operative mortality between groups (P=0.46). However, intensive care unit (ICU) and hospital stays were shorter in Group 1 (P=0.03 and <0.001, respectively). NYHA class improved significantly in both groups at one year (P<0.001 for both groups). There was no group effect on survival (P=0.84) or cardiac readmission (P=0.26). However, reoperations were more frequent in Group 1 (P=0.01). Conclusion: Transcatheter mitral valve-in-valve could shorten ICU and hospital stay compared to rSMVR with a comparable mortality rate. rTMVR is a safe procedure; however, it has a higher risk of reoperation. rTMVR can be an option in selected high-risk patients.

16.
Braz J Cardiovasc Surg ; 38(1): 52-61, 2023 02 10.
Article in English | MEDLINE | ID: mdl-36112740

ABSTRACT

INTRODUCTION: Repeat transcatheter mitral valve replacement (rTMVR) has emerged as a new option for the management of high-risk patients unsuitable for repeat surgical mitral valve replacement (rSMVR). The aim of this study was to compare hospital outcomes, survival, and reoperations after rTMVR versus surgical mitral valve replacement. METHODS: We compared patients who underwent rTMVR (n=22) from 2017 to 2019 (Group 1) to patients who underwent rSMVR (n=98) with or without tricuspid valve surgery from 2009 to 2019 (Group 2). We excluded patients who underwent a concomitant transcatheter aortic valve replacement or other concomitant surgery. RESULTS: Patients in Group 1 were significantly older (72.5 [67-78] vs. 57 [52-64] years, P<0.001). There was no diference in EuroSCORE II between groups (6.56 [5.47-8.04] vs. 6.74 [4.28-11.84], P=0.86). Implanted valve size was 26 (26-29) mm in Group 1 and 25 (25-27) mm in Group 2 (P=0.106). There was no diference in operative mortality between groups (P=0.46). However, intensive care unit (ICU) and hospital stays were shorter in Group 1 (P=0.03 and <0.001, respectively). NYHA class improved significantly in both groups at one year (P<0.001 for both groups). There was no group effect on survival (P=0.84) or cardiac readmission (P=0.26). However, reoperations were more frequent in Group 1 (P=0.01). CONCLUSION: Transcatheter mitral valve-in-valve could shorten ICU and hospital stay compared to rSMVR with a comparable mortality rate. rTMVR is a safe procedure; however, it has a higher risk of reoperation. rTMVR can be an option in selected high-risk patients.


Subject(s)
Heart Valve Prosthesis Implantation , Transcatheter Aortic Valve Replacement , Humans , Mitral Valve/surgery , Heart Valve Prosthesis Implantation/methods , Treatment Outcome , Transcatheter Aortic Valve Replacement/adverse effects , Reoperation , Aortic Valve/surgery , Retrospective Studies , Risk Factors
17.
Angiology ; 74(7): 664-671, 2023 Aug.
Article in English | MEDLINE | ID: mdl-35968605

ABSTRACT

Currently, there is no preference for surgical (SAVR) vs transcatheter (TAVR) aortic valve replacement in patients with low ejection fraction (EF). The present study retrospectively compared the outcomes of SAVR vs TAVR in patients with EF ≤40% (70 SAVR and 117 TAVR patients). Study outcomes were survival and the composite endpoint of stroke, aortic valve reintervention, and heart failure readmission. The patients who had TAVR were older (median: 75 (25-75th percentiles: 69-81) vs 51 (39-66) years old; P < .001) with higher EuroSCORE II (4.95 (2.99-9.85) vs 2 (1.5-3.25); P < .001). Postoperative renal impairment was more common with SAVR (8 (12.5%) vs 4 (3.42%); P = .03), and they had longer hospital stay [9 (7-15) vs 4 (2-8) days; P < .001). There was no difference between groups in stroke, reintervention, and readmission (Sub-distributional Hazard ratio: .95 (.37-2.45); P = .92). Survival at 1 and 5 years was 95% and 91% with SAVR and 89% and 63% with TAVR. Adjusted survival was comparable between groups. EF improved significantly (ß: .28 (.23-.33); P < 0.001) with no difference between groups (P = .85). In conclusion, TAVR could be as safe as SAVR in patients with low EF.


Subject(s)
Aortic Valve Stenosis , Heart Valve Prosthesis Implantation , Stroke , Transcatheter Aortic Valve Replacement , Humans , Adult , Middle Aged , Aged , Transcatheter Aortic Valve Replacement/adverse effects , Retrospective Studies , Aortic Valve Stenosis/surgery , Stroke Volume , Aortic Valve/surgery , Stroke/surgery , Treatment Outcome , Risk Factors
18.
ACS Omega ; 7(50): 46079-46089, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36570315

ABSTRACT

Remazol Brilliant Blue R (RBBR) is a common dye used in the industry, and its presence in wastewater and discharge into the environment can create a serious concern for the ecosystem and human health. Activated carbon produced from crop residues has emerged as a promising technique for removing contaminants from wastewater. In this study, leaf sheath date palm fiber-based activated carbon (LSDAC) was synthesized via phosphoric acid, H3PO4, treatment, followed by a microwave-induced carbonization process. The produced LSDAC was found to have a BET surface area of 604.61 m2/g, a Langmuir surface area of 922.05 m2/g, a total pore volume of 0.35 cm3/g, and an average pore size of 2.75 nm. The highest removal of RBBR was achieved at a solution pH of 3 (92.56 mg/g) and a solution temperature of 50 °C (90.37 mg/g). Adsorption of RBBR onto LSDAC followed the Langmuir isotherm model with a maximum monolayer capacity, Q m, of 243.43 mg/g, whereas in terms of kinetics, this adsorption system was best described by the pseudo-first-order (PFO) model. The calculated thermodynamic parameters ΔH°, ΔS°, ΔG°, and Arrhenius activation energy, E a, were 4.71 kJ/mol, 0.10 kJ/mol·K, -26.25 kJ/mol, and 5.88 kJ/mol, respectively, indicating that the adsorption of RBBR onto LSDAC was endothermic in nature, exhibited increased randomness at the solid-liquid interface, and was spontaneous and controlled by physisorption.

19.
Polymers (Basel) ; 14(16)2022 Aug 17.
Article in English | MEDLINE | ID: mdl-36015604

ABSTRACT

Calcium oxide (CaO) nanoparticles have recently gained much interest in recent research due to their remarkable catalytic activity in various chemical transformations. In this article, a chitosan calcium oxide nanocomposite was created by the solution casting method under microwave irradiation. The microwave power and heating time were adjusted to 400 watts for 3 min. As it suppresses particle aggregation, the chitosan (CS) biopolymer acted as a metal oxide stabilizer. In this study, we aimed to synthesize, characterize, and investigate the catalytic potency of chitosan-calcium oxide hybrid nanocomposites in several organic transformations. The produced CS-CaO nanocomposite was analyzed by applying different analytical techniques, including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM). In addition, the calcium content of the nanocomposite film was measured using energy-dispersive X-ray spectroscopy (EDS). Fortunately, the CS-CaO nanocomposite (15 wt%) was demonstrated to be a good heterogeneous base promoter for high-yield thiazole production. Various reaction factors were studied to maximize the conditions of the catalytic technique. High reaction yields, fast reaction times, and mild reaction conditions are all advantages of the used protocol, as is the reusability of the catalyst; it was reused multiple times without a significant loss of potency.

20.
J Card Surg ; 37(12): 4227-4233, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36040616

ABSTRACT

BACKGROUND: The debate about the optimal mitral valve prosthesis continues. We aimed to compare the early and late outcomes, including stroke, bleeding, survival, and reoperation after isolated mitral valve replacement (MVR) using tissue versus mechanical valves. METHODS: This retrospective cohort study included 291 patients who had isolated MVR from 2005 to 2015. Patients were grouped into the tissue valve group (n = 140) and the mechanical valve group (n = 151). RESULTS: There were no differences in duration of mechanical ventilation, hospital stay, and hospital mortality between groups. Fifteen patients required cardiac rehospitalization, nine in the tissue valve group, and six in the mechanical valve group (p = .44). Stroke occurred in nine patients, five with tissue valves, and four with mechanical valves (p = .66). Bleeding occurred in 22 patients, seven patients with tissue valves, and 15 patients with mechanical valves (p = .09). Freedom from reoperation was 95%, 93%, 84%, 67% at 3, 5, 7, and 10 years for tissue valve and 97%, 96%, 96%, and 93% for mechanical valves, respectively (p˂ .001). The median follow-up was 84 months (Q1: Q3: 38-139). Survival at 3, 5, 7, and 10 years was 94%, 91%, 89%, 86% in tissue valves and 96%, 93%, 91%, 91% in mechanical valves, respectively (p = .49). CONCLUSIONS: Tissue valve degeneration is still an issue even in the new generations of mitral tissue valves. The significant risk of reoperation in patients with mitral tissue valves should be considered when using those valves in younger patients. Mechanical valves remain a valid option for all age groups.


Subject(s)
Bioprosthesis , Heart Valve Diseases , Heart Valve Prosthesis Implantation , Heart Valve Prosthesis , Stroke , Humans , Mitral Valve/surgery , Heart Valve Prosthesis Implantation/adverse effects , Retrospective Studies , Treatment Outcome , Heart Valve Prosthesis/adverse effects , Hemorrhage/etiology , Stroke/etiology , Reoperation , Aortic Valve/surgery
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