Emulsion Liquid Membranes Based on Os-NP/n-Decanol or n-Dodecanol Nanodispersions for p-Nitrophenol Reduction

Membrane materials with osmium nanoparticles have been recently reported for bulk membranes and supported composite membrane systems. In the present paper, a catalytic material based on osmium dispersed in n-decanol (nD) or n-dodecanol (nDD) is presented, which also works as an emulsion membrane. The hydrogenation of p-nitrophenol (PNP) is carried out in a reaction and separation column in which an emulsion in the acid-receiving phase is dispersed in an osmium nanodispersion in n-alcohols. The variables of the PNP conversion process and p-aminophenol (PAP) transport are as follows: the nature of the membrane alcohol, the flow regime, the pH difference between the source and receiving phases and the number of operating cycles. The conversion results are in all cases better for nD than nDD. The counter-current flow regime is superior to the co-current flow. Increasing the pH difference between the source and receiving phases amplifies the process. The number of operating cycles is limited to five, after which the regeneration of the membrane dispersion is required. The apparent catalytic rate constant (kapp) of the new catalytic material based on the emulsion membrane with the nanodispersion of osmium nanoparticles (0.1 × 10-3 s-1 for n-dodecanol and 0.9 × 10-3 s-1 for n-decanol) is lower by an order of magnitude compared to those based on adsorption on catalysts from the platinum metal group. The advantage of the tested membrane catalytic material is that it extracts p-aminophenol in the acid-receiving phase.

Simultaneously Recovery of Thorium and Tungsten through Hybrid Electrolysis-Nanofiltration Processes

The recovery and recycling of metals that generate toxic ions in the environment is of particular importance, especially when these are tungsten and, in particular, thorium. The radioactive element thorium has unexpectedly accessible domestic applications (filaments of light bulbs and electronic tubes, welding electrodes, and working alloys containing aluminum and magnesium), which lead to its appearance in electrical and electronic waste from municipal waste management platforms. The current paper proposes the simultaneous recovery of waste containing tungsten and thorium from welding electrodes. Simultaneous recovery is achieved by applying a hybrid membrane electrolysis technology coupled with nanofiltration. An electrolysis cell with sulphonated polyether-ether-ketone membranes (sPEEK) and a nanofiltration module with chitosan-polypropylene membranes (C-PHF-M) are used to carry out the hybrid process. The analysis of welding electrodes led to a composition of W (tungsten) 89.4%; Th 7.1%; O2 2.5%; and Al 1.1%. Thus, the parameters of the electrolysis process were chosen according to the speciation of the three metals suggested by the superimposed Pourbaix diagrams. At a constant potential of 20.0 V and an electrolysis current of 1.0 A, the pH is varied and the possible composition of the solution in the anodic workspace is analyzed. Favorable conditions for both electrolysis and nanofiltration were obtained at pH from 6 to 9, when the soluble tungstate ion, the aluminum hydroxide, and solid thorium dioxide were formed. Through the first nanofiltration, the tungstate ion is obtained in the permeate, and thorium dioxide and aluminum hydroxide in the concentrate. By adding a pH 13 solution over the two precipitates, the aluminum is solubilized as sodium aluminate, which will be found after the second nanofiltration in the permeate, with the thorium dioxide remaining integrally (within an error of ±0.1 ppm) on the C-PHF-M membrane.

Thorium Removal, Recovery and Recycling: A Membrane Challenge for Urban Mining

Although only a slightly radioactive element, thorium is considered extremely toxic because its various species, which reach the environment, can constitute an important problem for the health of the population. The present paper aims to expand the possibilities of using membrane processes in the removal, recovery and recycling of thorium from industrial residues reaching municipal waste-processing platforms. The paper includes a short introduction on the interest shown in this element, a weak radioactive metal, followed by highlighting some common (domestic) uses. In a distinct but concise section, the bio-medical impact of thorium is presented. The classic technologies for obtaining thorium are concentrated in a single schema, and the speciation of thorium is presented with an emphasis on the formation of hydroxo-complexes and complexes with common organic reagents. The determination of thorium is highlighted on the basis of its radioactivity, but especially through methods that call for extraction followed by an established electrochemical, spectral or chromatographic method. Membrane processes are presented based on the electrochemical potential difference, including barro-membrane processes, electrodialysis, liquid membranes and hybrid processes. A separate sub-chapter is devoted to proposals and recommendations for the use of membranes in order to achieve some progress in urban mining for the valorization of thorium.

Hydrogen Sulphide Sequestration with Metallic Ions in Acidic Media Based on Chitosan/sEPDM/Polypropylene Composites Hollow Fiber Membranes System

This paper presents the preparation and characterization of composite membranes based on chitosan (Chi), sulfonated ethylene-propylene-diene terpolymer (sEPDM), and polypropylene (PPy), and designed to capture hydrogen sulfide. The Chi/sEPDM/PPy composite membranes were prepared through controlled evaporation of a toluene dispersion layer of Chi:sEPDM 1;1, w/w, deposited by immersion and under a slight vacuum (100 mmHg) on a PPy hollow fiber support. The composite membranes were characterized morphologically, structurally, and thermally, but also from the point of view of their performance in the process of hydrogen sulfide sequestration in an acidic media solution with metallic ion content (Cu²⁺, Cd²⁺, Pb²⁺, and/or Zn²⁺). The operational parameters of the pertraction were the pH, pM, matrix gas flow rate, and composition. The results of pertraction from synthetic gases mixture (nitrogen, methane, carbon dioxide) indicated an efficient removal of hydrogen sulfide through the prepared composite membranes, as well as its immobilization as sulfides. The sequestration and the recuperative separation, as sulfides from an acid medium, of the hydrogen sulfide reached up to 96%, decreasing in the order: CuS > PbS > CdS > ZnS.

Chitosan-sEPDM and Melatonin-Chitosan-sEPDM Composite Membranes for Melatonin Transport and Release

Melatonin is the hormone that focuses the attention of the researchers in the medical, pharmaceutical, materials, and membranes fields due to its multiple biomedical implications. The variety of techniques and methods for the controlled release of melatonin is linked to the multitude of applications, among which sports medicine occupies a special place. This paper presents the preparation and characterization of composite membranes based on chitosan (Chi) and sulfonated ethylene-propylene-diene terpolymer (sEPDM). The membranes were obtained by controlled vacuum evaporation from an 8% sEPDM solution in toluene (w/w), in which chitosan was dispersed in an ultrasonic field (sEPDM:Chi = 1:1, w/w). For the comparative evaluation of the membranes' performances, a melatonin-chitosan-sulfonated ethylene-propylene-diene terpolymer (Mel:Chi:sEPDM = 0.5:0.5:1.0, w/w/w) test membrane was made. The prepared membranes were morphologically and structurally characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy analysis (EDAX), thermal analysis (TG, DSC), thermal analysis coupled with chromatography and infrared analysis, and contact angle measurements, but also from the point of view of performance in the process of transport and release of melatonin in dedicated environments (aqueous solutions with controlled pH and salinity). The prepared membranes can release melatonin in amounts between 0.4 mg/cm²·per day (sEPDM), 1.6 mg/ cm²·per day (Chi/sEPDM), and 1.25 mg/cm²·per day (Mel/Chi/SEPDM).

Characterization of the Toxicological Impact of Heavy Metals on Human Health in Conjunction with Modern Analytical Methods

Increased environmental pollution, urbanization, and a wide variety of anthropogenic activities have led to the release of toxic pollutants into the environment, including heavy metals (HMs). It has been found that increasing concentrations of HMs lead to toxicity, mineral imbalances, and serious diseases, which are occurring more and more frequently. Therefore, testing has become imperative to detect these deficiencies in a timely manner. The detection of traces of HMs, especially toxic ones, in human tissues, various biological fluids, or hair is a complex, high-precision analysis that enables early diagnosis, addressing people under constant stress or exposed to a toxic environment; the test also targets people who have died in suspicious circumstances. Tissue mineral analysis (TMA) determines the concentration of toxic minerals/metals at the intracellular level and can therefore determine correlations between measured concentrations and imbalances in the body. Framing the already-published information on the topic, this review aimed to explore the toxicity of HMs to human health, the harmful effects of their accumulation, the advantages vs. the disadvantages of choosing different biological fluids/tissues/organs necessary for the quantitative measurement of HM in the human body, as well as the choice of the optimal method, correlated with the purpose of the analysis.

Obtaining and Characterizing the Osmium Nanoparticles/n-Decanol Bulk Membrane Used for the p-Nitrophenol Reduction and Separation System

Liquid membranes based on nanoparticles follow a continuous development, both from obtaining methods and characterization of techniques points of view. Lately, osmium nanoparticles have been deposited either on flat membranes, with the aim of initiating some reaction processes, or on hollow fiber membranes, with the aim of increasing the contact surface with the phases of the membrane system. This paper presents the obtainment and characterization of a liquid membrane based on osmium nanoparticles (Os-NP) dispersed in ndecanol (nDol) for the realization of a membrane system with a large contact surface between the phases, but without using a liquid membrane support. The dispersion of osmium nanoparticles in n-decanol is carried out by the method of reducing osmium tetroxide with 1-undecenoic acid (UDA). The resulting membrane was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive spectroscopy analysis (EDAX), thermoanalysis (TG, DSC), Fourier transform infra-red (FTIR) spectroscopy and dynamic light scattering (DLS). In order to increase the mass transfer surface, a design for the membrane system was realized with the dispersion of the membrane through the receiving phase and the dispersion of the source phase through the membrane (DBLM-dispersion bulk liquid membrane). The process performance was tested for the reduction of p-nitrophenol (pNP) from the source phase, using sodium tetra-borohydride (NaBH₄), to p-aminophenol (pAP), which was transported and collected in the receiving phase. The obtained results show that membranes based on the dispersion of osmium nanoparticles in n-decanol can be used with an efficiency of over 90% for the reduction of p-nitrophenol and the separation of p-aminophenol.

The Effects of the 'Catabolic Crisis' on Patients' Prolonged Immobility after COVID-19 Infection

Background and Objectives: Quarantine, isolation and bed rest associated with COVID-19 infection favored the loss of muscle and bone mass, especially in elderly patients. The current study aims to compare the presence of sarcopenia and osteoporosis in patients with a recent (one month) history of SARS-CoV-2 infection versus the general population. Materials and Methods: A cross-sectional study was conducted in which 157 patients were enrolled, divided into two groups, comparable in structure. The COVID-19 group (group C) consisted of 86 patients who were diagnosed with SARS-CoV-2 respiratory infection within the last 30 days. The non-COVID-19 group (group NC) consists of 71 patients who had no clinical signs of respiratory infection and were not quarantined/hospitalized in the last 3 months. Muscle strength, incidence of sarcopenia (using SARC-F score) and osteoporosis (DEXA determination) and physical performance (SPPB score) in the two groups were assessed and compared. Results: No statistically significant differences were found between the SPPB scores of the C group versus the NC group. Statistically significant differences were found in the evaluation of three parameters included in the SARC-F score. Patients in the C group had difficulties in standing up from a chair (p = 0.009) and climbing stairs (p = 0.030) due to lower muscle strength (p = 0.002) compared with patients in the NC group. No correlation of the SARC F and SPPB scores with the T score values obtained by osteo-densitometry was found. Conclusions: The sudden and significant reduction in physical activity, through various measures taken in the general population during the pandemic, led to an increased incidence of sarcopenia, both in patients who did not have COVID-19 infection and among those quarantined/hospitalized for this condition.

Non-conventional therapeutical approaches to acne vulgaris related to its association with metabolic disorders

The ever-increasing frequency of metabolic syndrome (MetS) is still a major challenge of the public health care system, worldwide. In recent years, researchers have been drawn to the uncommon (at first look) link between skin illnesses and MetS. Because of the pro-inflammatory mechanisms and insulin resistance (IR) that are upregulated in metabolic syndrome, many skin disorders are correlated to metabolic dysfunctions, including acne vulgaris. A comprehensive understanding of the link between MetS and acne vulgaris may contribute to the development of new treatment strategies. The current review focuses on dietary and therapeutic interventions and assesses the effect of various approaches such as improving diet by avoiding certain food products (i.e., milk and chocolate) or increasing the intake of others (i.e., food products rich in omega-3 fatty acids), metformin administration, therapy with plant extracts, plant essential oils, and probiotic supplementation on the improvement of certain acne vulgaris severity parameters. These therapeutic approaches, when combined with allopathic treatment, can improve the patients' quality of life.

A Narrative Review of the Classical and Modern Diagnostic Methods of the No-Reflow Phenomenon

The incidence of the no-reflow (NR) phenomenon varies depending on the diagnostic criteria used. If just the angiographic criteria are considered (i.e., a degree of thrombolysis in myocardial infarction ≤2), it will be found that the incidence of NR is quite low; on the other hand, when the myocardial NR is taken into account (i.e., a decrease in the quality of myocardial reperfusion expressed by the degree of myocardial blush), the real incidence is higher. Thus, the early establishment of a diagnosis of NR and the administration of specific treatment can lead to its reversibility. Otherwise, regardless of the follow-up period, patients with NR have a poor prognosis. In the present work, we offer a comprehensive perspective on diagnostic tools for NR detection, for improving the global management of patients with arterial microvasculature damage, which is a topic of major interest in the cardiology field, due to its complexity and its link with severe clinical outcomes.

Therapeutic dilemmas in addressing SARS-CoV-2 infection: Favipiravir versus Remdesivir

Coronavirus disease 2019 (COVID-19) represents an unmet clinical need, due to a high mortality rate, rapid mutation rate in the virus, increased chances of reinfection, lack of effectiveness of repurposed drugs and economic damage. COVID-19 pandemic has created an urgent need for effective molecules. Clinically proven efficacy and safety profiles have made favipiravir (FVP) and remdesivir (RDV) promising therapeutic options for use against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Even though both are prodrug molecules with an antiviral role based on a similar mechanism of action, differences in pharmacological, pharmacokinetic and pharmacotoxicological mechanisms have been identified. The present study aims to provide a comprehensive comparative assessment of FVP and RDV against SARS-CoV-2 infections, by centralizing medical data provided by significant literature and authorized clinical trials, focusing on the importance of a better understanding of the interactions between drug molecules and infectious agents in order to improve the global management of COVID-19 patients and to reduce the risk of antiviral resistance.

Operational Limits of the Bulk Hybrid Liquid Membranes Based on Dispersion Systems

Liquid membranes usually have three main constructive variants: bulk liquid membranes (BLM), supported liquid membranes (SLM) and emulsion liquid membranes (ELM). Designing hybrid variants is very topical, with the main purpose of increasing the flow of substance through the membrane but also of improving the selectivity. This paper presents the operational limits of some kind of hybrid membrane constituted as a bulk liquid membrane (BLM), but which works by dispersing the aqueous source (SP) and receiving (RP) phases, with the membrane itself being a dispersion of nanoparticles in an organic solvent (NP–OSM). The approached operational parameters were the volume of phases of the hybrid membrane system, the thickness of the liquid membrane, the working temperature, the flow of aqueous phases, the droplet size of the aqueous phases dispersed across the membrane, the nature and concentration of nanoparticles in the membrane, the pH difference between the aqueous phases, the nature of the organic solvent, the salt concentration in the aqueous phases and the nature of transported chemical species. For this study, silver ion (SI) and p-nitrophenol (PNP) were chosen as transportable chemical species, the n-aliphatic alcohols (C6…C12) as membrane organic solvents, 10–undecenoic acid (UDAc) and 10-undecylenic alcohol (UDAl) as carriers and magnetic iron oxides as nanoparticles dispersed in the membrane phase. Under the experimentally established operating conditions, separation efficiencies of over 90% were obtained for both ionic and molecular chemical species (silver ions and p-nitrophenol). The results showed the possibility of increasing the flow of transported chemical species by almost 10 times for the silver ion and approximately 100 times for p-nitrophenol, through the appropriate choice of operational parameters, but they also exposed their limits in relation to the stability of the membrane system.

Highlighting the advantages and benefits of cementless total knee arthroplasty (Review)

In the field of orthopedic surgery, cemented total knee arthroplasty (TKA) is considered to be one of the gold standards. However, there are categories of patients (i.e., obese and morbidly obese patients, younger than 65 years old) among whom cemented TKA has however a high failure rate. Moreover, the frequency of using uncemented TKA is increasing due to the potential benefits of long-term biological fixation, being an innovative field that addresses a new generation orthopedic surgical treatment which is more suitable for young patients who have good bone quality (good to very good, in terms of density). The survival rates and functional results of the latest generation of cementless TKAs may be similar to functional results and survival rates of cemented prosthesis. In conclusion, this review-type article can be considered a powerful database, extremely informative, dense, and focused on the topic mentioned above, in the interest of all medical professionals and all interested individuals.

Comorbidities, Associated Diseases, and Risk Assessment in COVID-19-A Systematic Review

It is considered that COVID-19's pandemic expansion is responsible for the particular increase in deaths, especially among the population with comorbidities. The health system is often overwhelmed by the large number of cases of patients addressing it, by the regional limitation of funds, and by the gravity of cases at subjects suffering from this pathology. Several associated conditions including diabetes, cardiovascular illnesses, obesity, persistent lung condition, neurodegenerative diseases, etc., increase the mortality risk and hospitalization of subjects suffering from COVID-19. The rapid identification of patients with increased risk of death from the SARS-CoV-2 virus, the stratification in accordance with the risk and the allocation of human, financial, and logistical resources in proportion must be a priority for health systems worldwide.

Osmium Recovery as Membrane Nanomaterials through 10-Undecenoic Acid Reduction Method

The recovery of osmium from residual osmium tetroxide (OsO₄) is a necessity imposed by its high toxicity, but also by the technical-economic value of metallic osmium. An elegant and extremely useful method is the recovery of osmium as a membrane catalytic material, in the form of nanoparticles obtained on a polymeric support. The subject of the present study is the realization of a composite membrane in which the polymeric matrix is the polypropylene hollow fiber, and the active component consists of the osmium nanoparticles obtained by reducing an alcoholic solution of osmium tetroxides directly on the polymeric support. The method of reducing osmium tetroxide on the polymeric support is based on the use of 10-undecenoic acid (10-undecylenic acid) (UDA) as a reducing agent. The osmium tetroxide was solubilized in t-butanol and the reducing agent, 10-undecenoic acid (UDA), in i-propanol, t-butanol or n-decanol solution. The membranes containing osmium nanoparticles (Os-NP) were characterized morphologically by the following: scanning electron microscopy (SEM), high-resolution SEM (HR-SEM), structurally: energy-dispersive spectroscopy analysis (EDAX), Fourier transform infrared (FTIR) spectroscopy. In terms of process performance, thermal gravimetric analysis was performed by differential scanning calorimetry (TGA, DSC) and in a redox reaction of an organic marker, p-nitrophenol (PNP) to p-aminophenol (PAP). The catalytic reduction reaction with sodium tetraborate solution of PNP to PAP yielded a constant catalytic rate between 2.04 × 10^-4 mmol s^-1 and 8.05 × 10^-4 mmol s^-1.

Chemo-Preventive Action of Resveratrol: Suppression of p53-A Molecular Targeting Approach

Extensive experimental, clinical, and epidemiological evidence has explained and proven that products of natural origin are significantly important in preventing and/or ameliorating various disorders, including different types of cancer that researchers are extremely focused on. Among these studies on natural active substances, one can distinguish the emphasis on resveratrol and its properties, especially the potential anticancer role. Resveratrol is a natural product proven for its therapeutic activity, with remarkable anti-inflammatory properties. Various other benefits/actions have also been reported, such as cardioprotective, anti-ageing, antioxidant, etc. and its rapid digestion/absorption as well. This review aims to collect and present the latest published studies on resveratrol and its impact on cancer prevention, molecular signals (especially p53 protein participation), and its therapeutic prospects. The most recent information regarding the healing action of resveratrol is presented and concentrated to create an updated database focused on this topic presented above.

Chemical Profile, Antioxidant Capacity, and Antimicrobial Activity of Essential Oils Extracted from Three Different Varieties (Moldoveanca 4, Vis Magic 10, and Alba 7) of Lavandula angustifolia

Chemical composition, antioxidant capacity, and antimicrobial activity of lavender essential oils (LEOs) extracted from three different varieties of Lavandula angustifolia Mill. (1-Moldoveanca 4, 2-Vis magic 10, and 3-Alba 7) have been determined. These plants previously patented in the Republic of Moldova were cultivated in an organic agriculture system in the northeastern part of Romania and then harvested in 3 consecutive years (2017-2019) to obtain the essential oils. From the inflorescences in the complete flowering stage, the LEOs were extracted by hydrodistillation. Then, their composition was analyzed by gas chromatography coupled with mass spectrometry (GC-MS) and by Fourier Transformed Infrared spectroscopy (FT-IR). The major identified constituents are as follows: linalool (1: 32.19-46.83%; 2: 29.93-30.97%; 3: 31.97-33.77%), linalyl acetate (1: 17.70-35.18%; 2: 27.55-37.13%; 3: 28.03-35.32%), and terpinen-4-ol (1: 3.63-7.70%; 2: 3.06-7.16%; 3: 3.10-6.53%). The antioxidant capacity as determined by ABTS and DPPH assays indicates inhibition, with the highest activity obtained for LEO var. Alba 7 from 2019. The in vitro antimicrobial activities of the LEOs and combinations were investigated as well, by using the disk diffusion method and minimum inhibitory concentration (MIC) against the Gram-positive bacterial strain Staphylococcus aureus (ATCC 6538), Gram-negative Pseudomonas aeruginosa (ATCC 27858), Escherichia coli (ATCC 25922), the yeast Candida albicans (ATCC 10231), and clinical isolates. Our results have shown that LEOs obtained from the three studied varieties of L. angustifolia manifest significant bactericidal effects against tested microorganisms (Staphylococcus aureus and Escherichia coli), and antifungal effects against Candida albicans. The mixture of LEOs (Var. Alba 7) and geranium, respectively, in tea tree EOs, in different ratios, showed a significant enhancement of the antibacterial effect against all the studied strains, except Pseudomonas aeruginosa.

The Footprint of Kynurenine Pathway in Neurodegeneration: Janus-Faced Role in Parkinson's Disorder and Therapeutic Implications

Progressive degeneration of neurons and aggravation of dopaminergic neurons in the substantia nigra pars compacta results in the loss of dopamine in the brain of Parkinson's disease (PD) patients. Numerous therapies, exhibiting transient efficacy have been developed; however, they are mostly accompanied by side effects and limited reliability, therefore instigating the need to develop novel optimistic treatment targets. Significant therapeutic targets have been identified, namely: chaperones, protein Abelson, glucocerebrosidase-1, calcium, neuromelanin, ubiquitin-proteasome system, neuroinflammation, mitochondrial dysfunction, and the kynurenine pathway (KP). The role of KP and its metabolites and enzymes in PD, namely quinolinic acid (QUIN), kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), 3-hydroxyanthranillic acid (3-HAA), kunurenine-3-monooxygenase (KMO), etc. has been reported. The neurotoxic QUIN, N-methyl-D-aspartate (NMDA) receptor agonist, and neuroprotective KYNA-which antagonizes QUIN actions-primarily justify the Janus-faced role of KP in PD. Moreover, KP has been reported to play a biomarker role in PD detection. Therefore, the authors detail the neurotoxic, neuroprotective, and immunomodulatory neuroactive components, alongside the upstream and downstream metabolic pathways of KP, forming a basis for a therapeutic paradigm of the disease while recognizing KP as a potential biomarker in PD, thus facilitating the development of a suitable target in PD management.

Improving the Performance of Composite Hollow Fiber Membranes with Magnetic Field Generated Convection Application on pH Correction

The membranes and membrane processes have succeeded in the transition from major technological and biomedical applications to domestic applications: water recycling in washing machines, recycling of used cooking oil, recovery of gasoline vapors in the pumping stations or enrichment of air with oxygen. In this paper, the neutralization of condensation water and the retention of aluminum from thermal power plants is studied using ethylene propylene diene monomer sulfonated (EPDM-S) membranes containing magnetic particles impregnated in a microporous propylene hollow fiber (I-PPM) matrix. The obtained membranes were characterized from the morphological and structural points of view, using scanning electron microscopy (SEM), high resolution SEM (HR-SEM), energy dispersive spectroscopy analysis (EDAX) and thermal gravimetric analyzer. The process performances (flow, selectivity) were studied using a variable magnetic field generated by electric coils. The results show the possibility of correcting the pH and removing aluminum ions from the condensation water of heating plants, during a winter period, without the intervention of any operator for the maintenance of the process. The pH was raised from an acidic one (2–4), to a slightly basic one (8–8.5), and the concentration of aluminum ions was lowered to the level allowed for discharge. Magnetic convection of the permeation module improves the pH correction process, but especially prevents the deposition of aluminum hydroxide on hollow fibers membranes.

Value of Hematological and Coagulation Parameters as Prognostic Factors in Acute Coronary Syndromes

The values of hematological and coagulation biomarkers were evaluated as predictors of in hospital mortality and complications, in patients with acute coronary syndromes (ACS). This retrospective observational study enrolled 936 ACS subjects admitted to the Clinical Emergency Hospital of Oradea, Romania, between January-December 2019. Hematological and coagulation parameters were obtained at admission. During hospitalization, the following adverse events were recorded: death, ventricular rhythm disturbances, atrial fibrillation, heart failure, re-infarction, and stroke. Accuracy of hematological and coagulation parameters as predictors of adverse outcome were also evaluated. The diagnosis was unstable angina in 442 patients (47.22%), non-ST-elevation myocardial infarction (NSTEMI) in 113 patients (12.1%) and ST-elevation myocardial infarction (STEMI) in 381 patients (40.70%); 87 patients (9.29%) died during hospitalization and 193 (20.7%) developed complications. Predictors for in hospital mortality were as follows: red cell distribution width (RDW) (AUC 0.691, p < 0.0001), white blood cells (WBC) (AUC 0.684, p < 0.0001), neutrophils (NEU) (AUC 0.684, p < 0.0001), and prothrombin time (PT) (AUC 0.765, p < 0.0001). WBC (AUC 0.659, p < 0.0001), NEU (AUC 0.664, p < 0.0001), RDW (AUC 0.669, p < 0.0001), and PT (AUC 0.669, 95% CI 0.622-0.714, p < 0.0001) also had accuracy for complications prediction. RDW had a good ability to predict heart failure in NSTEMI patients (AUC 0.832, p < 0.0001). An acceptable ability to predict ventricular rhythm disturbances occurrence had WBC (AUC 0.758, p < 0.0001) and NEU (AUC 0.772, p < 0.0001). Hematological and coagulation parameters can help in risk stratification of ACS patients. RDW, WBC, NEU, and PT were able to predict mortality and in-hospital complications in ACS patients. RDW has a good accuracy in predicting complications and heart failure in NSTEMI patients. WBC and NEU are good predictors for ventricular rhythm disturbances.

Removing of the Sulfur Compounds by Impregnated Polypropylene Fibers with Silver Nanoparticles-Cellulose Derivatives for Air Odor Correction

The unpleasant odor that appears in the industrial and adjacent waste processing areas is a permanent concern for the protection of the environment and, especially, for the quality of life. Among the many variants for removing substance traces, which give an unpleasant smell to the air, membrane-based methods or techniques are viable options. Their advantages consist of installation simplicity and scaling possibility, selectivity; moreover, the flows of odorous substances are direct, automation is complete by accessible operating parameters (pH, temperature, ionic strength), and the operation costs are low. The paper presents the process of obtaining membranes from cellulosic derivatives containing silver nanoparticles, using accessible raw materials (namely motion picture films from abandoned archives). The technique used for membrane preparation was the immersion precipitation for phase inversion of cellulosic polymer solutions in methylene chloride: methanol, 2:1 volume. The membranes obtained were morphologically and structurally characterized by scanning electron microscopy (SEM) and high resolution SEM (HR SEM), energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectrometry (FTIR), thermal analysis (TG, ATD). Then, the membrane performance process (extraction efficiency and species flux) was determined using hydrogen sulfide (H2S) and ethanethiol (C2H5SH) as target substances.

Recognizing the Benefits of Pre-/Probiotics in Metabolic Syndrome and Type 2 Diabetes Mellitus Considering the Influence of Akkermansia muciniphila as a Key Gut Bacterium

Metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) are diseases that can be influenced by the structure of gut microbiota, whose improvement is often neglected in metabolic pathology. This review highlights the following main aspects: the relationship between probiotics/gut microbes with the pathogenesis of MetS, the particular positive roles of Akkermansia muciniphila supplementation in the onset of MetS, and the interaction between dietary polyphenols (prebiotics) with gut microbiota. Therefore, an extensive and in-depth analysis of the often-neglected correlation between gut microbiota and chronic metabolic diseases was conducted, considering that this topic continues to fascinate and stimulate researchers through the discovery of novel strains and their beneficial properties.

Study the Effect of Gum Arabic and Triton X-100 on Stability and Thermal Conductivity of ZnO/ethylene glycol Nanofluids

Stability of nanofluids is one of the most important factors to ensure the most benefit of the properties of nanoparticles. Zinc oxide was used in the research with concentration between (0.2-1) wt. % with ethylene glycol base fluid. The stability of ZnO nanofluid was enhanced by adding two types of surfactants Tx-100 and Gum Arabic with concentration of (0.1-0.5) vol. % to stabilize the ZnO nanoparticles in the base fluid. The results showed that the Gum Arabic surfactant led to more stable fluid than that of Tx-100; this was shown from zeta potential and UV spectroscopy measurements. The thermal conductivity coefficient was also measured, and the results showed that the thermal conductivity increased with adding surfactant than without using a stabilizer.

Removal of Toxic Phenolic Compounds from Wastewater Using Zeolite (4A) Prepared from Local Clays Taken from the Slopes of the Tigris River

The massive scale of industrial development has resulted in environmental pollution in general and water contamination in particular. It is important at the present time to treat water for the purpose of eliminating or reducing pollutants, especially toxic pollutants, such as phenol compounds. In this study, zeolite (4A) was prepared firstly from the available and cheap materials using an inclined rotary disk. Then, physical, mechanical, and chemical properties were also studied. Experiments were conducted to determine these properties using local clay and the following results were obtained: Zeolite (4A) 70% and clay 30%, the time of calcination 3 h at a temperature of 850��C, breakage resistance of 17 Ib pounds, surface area 530-590 m2/g, grinding value 14% and moisture absorption ratio 30%. The prepared zeolite (4A) was used in the process of removing phenolic compounds (chlorophenol, nitrophenol) by the adsorption method. Different amounts of prepared zeolite (5g/l and 10g/L) will be used in the treatment process and different concentrations (2mg/L, 5 mg/L and 10 mg/L) of the pollutants Nitrophenol and Chlorophenol were used in the contaminated water tested. The removal process was carried out with a mixing speed of 200 rpm and pH (7.5-8.5). From the results of this study, we note that the highest percentage of Nitrophenol removal is (84.8%) when using an amount of zeolite (5g) and highest percentage of Nitrophenol removal is (95.5%) when using an amount of zeolite (10g) while that the highest percentage of Chlorophenol removal is (78.3%) when using an amount of zeolite (5g) and highest percentage of Chlorophenol removal is (0.894) when using an amount of zeolite (10g) it could be deduced that the percentage of the removal of nitrophenol was higher than that of chlorophenol because its solubility of chlorophenol in water is higher than the solubility of Nitrophenol.

Control of Nanostructured Polysulfone Membrane Preparation by Phase Inversion Method

The preparation of membranes from polymer solutions by the phase inversion method, the immersion—precipitation technique has proved since the beginning of obtaining technological membranes the most versatile and simple possibility to create polymeric membrane nanostructures. Classically, the phase inversion technique involves four essential steps: Preparation of a polymer solution in the desired solvent, the formation of the polymer solution film on a flat support, the immersion of the film in a coagulation bath containing polymer solvents, and membrane conditioning. All phase inversion stages are important for the prepared membrane’s nanostructure and have been studied in detail for more than six decades. In this paper, we explored, through an electrochemical technique, the influence of the contact time with the polymer film’s environment until the introduction into the coagulation bath. The system chosen for membrane preparation is polysulfone-dimethylformamide-aqueous ethanol solution (PSf-DMF-EW). The obtained nanostructured membranes were characterized morphologically and structurally by scanning electron microscopy (SEM) and thermal analysis (TA), and in terms of process performance through water permeation and bovine serum albumin retention (BSA). The membrane characteristics were correlated with the polymeric film exposure time to the environment until the contact with the coagulation bath, following the diagram of the electrochemical parameters provided by the electrochemical technique.

Eighteen Months Follow-Up with Patient-Centered Outcomes Assessment of Complete Dentures Manufactured Using a Hybrid Nanocomposite and Additive CAD/CAM Protocol

Abstract: The present study aimed to assess the eighteen month follow-up patient-centered outcomes of a simple and predictable protocol for 3D-printed functional complete dentures manufactured using an improved poly(methyl methacrylate) (PMMA)-nanoTiO2. A detailed morphological and structural characterization of the PMMA-TiO2 nanocomposite, using SEM, EDX, XRD, and AFM, after 3D-printing procedure and post-wearing micro-CT, was also performed.

METHODS

A total of 35 fully edentulous patients were enrolled in this prospective study. A 0.4% TiO2-nanoparticle-reinforced PMMA composite with improved mechanical strength, morphologically and structurally characterized, was used according to an additive computer-aided design and computer-aided manufacturing (CAD/CAM) protocol for complete denture fabrication. The protocol proposed involved a three-step appointment process. Before denture insertion, 1 week, 12 month, and 18-month follow up patients were evaluated via the Visual Analogue Scale (VAS, 0-10) and Oral Health Impact Profile for Edentulous Patients (OHIP-EDENT), with a higher score meaning poor quality of life.

RESULTS

A total of 45 complete denture sets were inserted. OHIP-EDENT scored significantly better after 18 months of denture wearing, 20.43 (±4.42) compared to 52.57 (±8.16) before treatment; mean VAS was improved for all parameters assessed.

CONCLUSIONS

Within the limitations of this study, we can state that the proposed workflow with the improved material used is a viable treatment option for patients diagnosed with complete edentulism.

Added value recyclability of glass fiber waste as photo-oxidation catalyst for toxic cytostatic micropollutants

There is an increased interest in recycling valuable waste materials for usage in procedures with high added values. Silica microparticles are involved in the processes of catalysis, separation, immobilization of complexants, biologically active compounds, and different nanospecies, responding to restrictive requirements for selectivity of various chemical and biochemical processes. This paper presents the surface modification of accessible and dimensionally controlled recycled silica microfiber with titanium dioxide. Strong base species in organic solvents: methoxide, ethoxide, propoxide, and potassium butoxide in corresponding alcohol, activated the glass microfibres with 12-13 µm diameter. In the photo-oxidation process of a toxic micro-pollutant, cyclophosphamide, the new composite material successfully proved photocatalytic effectiveness. The present work fulfills simultaneously two specific objectives related to the efforts directed towards a sustainable environment and circular economy: recycling of optical glass microfibers resulted as waste from the industry, and their usage for the photo-oxidation of highly toxic emerging micro-pollutants.

Model Driven Analysis of the Biosynthesis of 1,4-butanediol from Renewable Feedstocks in Escherichia coli

Bio-based, environmentally benign production of commodity chemicals such as 1,4-butanediol (BDO) from renewable feedstocks is highly challenging due to the lack of natural synthesis pathways. Herein, we present a systematic model-driven evaluation of the production potential for Escherichia coli to produce BDO from renewable carbohydrates (glucose, glycerol). Computational analysis was carried out in order to decipher the metabolic characteristics under various genetic and environmental conditions. Optimal strain designs were achieved using only two (adhE2- alcohol dehydrogenase and cat/sucCD- 4-hydroxybutyrate-CoA transferase/4-hydroxybutyryl-CoA ligase) heterologous reactions; highest yields were attained for: glucose ~0.37 g g-1 (3 knockouts, anaerobically) and glycerol ~0.43 g g-1 (4 knockouts, microaerobically). The maximum achievable production yield was over 95% of the theoretical maximum potential for glucose and over 75% for glycerol. In regards to the genome-scale metabolic model predictions, a metabolically engineered E. coli was created to analyze the new biosynthetic pathway stability and functionality. Considering the preliminary outcomes the strain and pathway is stable under fermentative conditions and a limited quantity of BDO ~1 mg L-1 was obtained, therefore long-term adaptive evolution is mandatory. This study outlines a strain design and analysis pipeline -systems biology-based approach- for non-native compounds production strains.

In silico Analysis of 1,4-butanediol Heterologous Pathway Impact on Escherichia coli Metabolism

The bio-based synthesis of 1,4-butanediol (BDO), a key compound in many industries, has recently been achieved in Escherichia coli, however the yield even in glucose was far below the theoretical maximum. Furthermore, the impact of the BDO pathway on cell metabolism is yet to be discovered. The main objective of this study was to in silico improve and analyze the production potential of BDO on glucose and glycerol and evaluate the interaction between native and non-native pathways for wild-type and mutant strains using a simple biosynthetic pathway. The maximum production potential and changes in metabolic fluxes were simulated by different objective functions (biomass and BDO) and the reactions with highest differences were identified under different environmental conditions. Considering the outcomes 80% of the reactions with significant flux change were identical for all conditions simulated. Flux variability analysis was carried out to decipher the variation of fluxes and flux span changes (SC) were calculated. To further analyse the reactions with SC over 1 mmol gDW-1h-1 and to calculate the correlation coefficients for WT and mutant strains uniform random sampling was carried out. Most important variations in correlation patterns were observed for reactions in the mutant model. On the other hand, the addition, elimination and optimization of different pathways significantly affected the pairwise correlation patterns as well as the entire solution space of the network.

Validation and Quality Assurance of Ascorbic Acid Determination in Agricultural Products

The study describes a method for the determination of ascorbic acid (AA) with the technique of high performance liquid chromatography with UV detection (UV-HPLC) modified for routine analysis of agricultural products. For successful use of the method in the test laboratory practice, the reliability of using this method has been confirmed by validation. The repeatability of method has been observed, which is 2.80 - 5.55% for the various crops. Relative combined standard uncertainty has a value of 6.2%. The accuracy of the method is 103.2% and calculated as recovery of the standard addition. The value of the LOQ computed from the upper limit of reliability is 26.7 mg kg-1, which ensures safe determination of AA in every major agricultural crop.

Innovative Complex Formulation as Topical Treatment for Oral Health Improvment in Periodontal Disease

A complex formulation for topical treatment, consisting of melatonin, hyaluronic acid, tetracycline, and metronidazole mixture is proposed as periodontal disease adjunctive treatment. In order to follow the structural aspects of the active mixture, spectrophotometric methods: UV-Vis and fluorescence, have been applied. The results obtained complete our previous studies. By adding metronidazole to the mixture composed of: melatonin, hyaluronic acid, and tetracycline, the conjugated effect of the active compounds, combining antimicrobial action with anti-inflammatory and immunomodulatory effect, is expected to significaly improve supportive therapy in moderate forms of periodontitis.

Removal of Dyes from Wastewater by Ceramic Membrane

The current study aimed to investigate the elimination of dyes from sewerage, using microfiltration membrane mechanism. Three dyes were applied, acid yellow-23, disperse blue -79 and acid orange -7. Experiments were performed with feed concentration (40 -120) ppm, feed flow rate (25 -65) l/h and time (0.25 -1.5) h. The membrane used ceramic membrane, constructed as a candle. It was discovered that water flow diminishes with an elevation in running time, feeding oil concentration and enhancing with elevation in the feed flow rate. In addition, it was determined that the elimination (rejection) rate of dyes enhances with elevation in the flow rate, and the elimination (rejection) rate diminishes as time passes. In cross flow microfiltration, the rejection concentration (concentrate) goes up as time passes, with high feed concentration and flow rate. It was also discovered that the modal infusion concentration declines with high feed concentration and working time. In addition, it was found that product rate goes down as time passes and with high feed concentration. Increasing feed concentration of dyes was associated with an increase in the concentration of rejecting solution. The highest elimination of disperse blue -79, Acid Yellow- 23 and acid orange -7, are 97%, 96.4% and 95.8%, respectively. The maximum recovery percentage of disperse blue - 79, acid yellow- 23 and acid orange -7are 57.7%, 58.5% and 59% respectively.

Determination of the Optimal Condition of Direct Blue Dye. Removal from Aqueous Solution Using Eggshell

Eggshells was used as a natural adsorbent to remove direct blue(DB) dye from aqueous solution and investigating the four factors that affect the adsorption of DB dye ; amount of eggshell rang (0.1 - 1g), initial concentration (10 - 60 mg/L ), time ( 5 - 45 min.) and pH (3 - 11). Central Composition Design with four variables and five levels coupled with response surface method was adopted to get a second order polynomial equation for dye removal percentage as the response, and to obtain the optimum conditions for maximum dye removal percentage ; which reach 84% with optimum point , eggshell (0.835 g) ,time (24min.) , initial dye concentration ( 10 mg/L) , pH (4.2). The most effecting factors on dye removal are pH and initial dye concentration. Langmuir, Freundich model gives good fitting with (R2 ]0.98). The process of adsorption of DB dye on eggshell fitted a pseudo-second order kinetic model.

Melatonin and Hyaluronic Acid in Periodontal Disease

The aim of the present paper was to highlight the individual effects of melatonin (MEL) and hyaluronic acid (HA) on periodontal structures and repair mechanism and to investigate a possible synergic effect and if each component of the proposed mixture (MEL-HA) would maintain their specific characteristics, when using booth active principles, for a topical application. A comprehensive review of the recent literature focusing on the role of MEL and HA in periodontal therapy, as well as on the use of both active compounds and possible synergic effect, have been conducted. An experimental investigation, using the FT-IR analysis, both the individual spectra of each component and the complex matrix obtained was performed. The experimental data obtained from our study proved that no structural changes occurred at the level of the functional groups of the components. Therefore, it is expected that the obtained formulation to be highly efficient for the treatment of periodontal disease, as it would combine the specific local action of MEL and HA.

Synthesis, Characterization and Antibacterial Activity from Mixed Ligand Complexes of 8-Hydroxyquinoline and Tributylphosphine for Some Metal Ions

Co+2, Ni+2, Cu+2 as well Zn+2 compounds mixed ligand from 8-hydroxyquinoline(8-HQ) also tributylphosphine (PBu3) have been attended at aquatic ethyl alcohol for (1:2:2) (M:8-HQ:PBu3). Produced complexes have been identified by utilizing atomic absorption flame, FT-IR as well UV-Vis spectrum manners also magnetic susceptibility as well as conductivity methods. At addendum antibacterial efficiency from the ligands as well complexes oboist three species about bacteria have been as well examined. Ligands and their complexes show good bacterial efficiencies. Of the gained datum the octahedral geometry was proposed into whole prepared complexes.

Coated copper Wire Calcium Selective Microelectrode for Applications in Dental Medicine

A coated wire calcium selective microelectrode for biological use was developed, comprising a PVC selective matrix containing calcium ionophore IV coated on copper wire, previously covered with a solid-state contact mixture. The obtained calcium microsensor presented a Nernstian answer in a concentration range of 10-1 to 10-6 mol/L. The selectivity coefficients over the main interfering ions of biological interest proved that the calcium microelectrode is highly selective. Also, the response time (6s) and repeatability have been determined. The pH variation did not significantly modify the calcium microelectrode answer, being stable over the pH range (6.7-7.3) of interest. The obtained calcium microelectrode is simple, inexpensive and able to give reliable electrochemical response, recommending itself as a solution for assessing the level of inorganic ions of the gingival crevicular fluid and saliva.

Isotherm and Kinetic Models for Bio-sorption of Cadmium Ions from Aqueous Solutions using Dry Peanut Shells and Hazelnut Shells

This work is aiming to investigate the removal Cd(II) ions from the aqueous solution using two types of biosorbent materials: peanut shells (PS) and hazelnut shells (HS). The effect of several variables on the batch bio-sorption was studied. The process was carried out at room temperature, shacking speed 200 rpm and using fixed adsorbent diameters of 0.75 mm. The highest removal efficiency of Cd(II) ions onto PS was 91.45% in the best conditions (pH=3, initial concentration of Cd(II) ions 50 mg/ L, amount adsorbent was 0.75 g, contact time was 120 min), while the highest removal efficiency when using HS was 85.62% at pH= 4, and contact time of 160 minutes using the same initial concentration of Cd(II) ions as well as the same amount of absorbent material. Isotherm was studied for bio-sorption of Cd(II) ions using these two adsorbents, and the pseudo- first and second order models were used to study bio-sorption kinetics. The results of the infrared spectroscopy (FTIR) of (PS) and (HS) samples before and after loading for Cd(II) ions showed that hydroxyl and carboxyl groups play a major role in bio-sorption of these ions.

Use of Artificial Neural Network for Modeling and Prediction of Reactive Red Dye Removal from Wastewater Using Banana Peels Bio-sorbent

Bio-sorption of red dye from aqueous solutions onto banana peels was investigated. Effects of initial pH, bio-sorbent dose, initial concentration, contact time, and temperature were studied and they found of 3, 0.4 g/100 mL, 50 mg/L, 100 min and 298 K respectively with removal efficiency of 93.44%. Artificial neural network was used for prediction of adsorption efficiency and its outputs showed a better fit than other traditional isotherm models. The negative values of DG� and DH� indicate that the bio-sorption of red dye was favored and exothermic. The sensitivity analysis signified that the pH was the most influential variable.

Evolution of Tropospheric Ozone and Relationship with Temperature and NOx for the 2007-2016 Decade in the Ciuc Depression

This paper presents the evolution of ozone concentration for the 2007-2016 decade and a comparison with key values related to human and vegetation health. As temperature is one of the main factors influencing ozone concentration in this area, the most significant changes of air temperature and extreme temperature indices for the 2007 - 2016 decade were evaluated, in retrospect to temperature measurements for the 1961-1990 reference period. The relationship between temperature and ozone concentration was also overviewed, by means of climate penalty factor. The influence of NOx concentration on ozone concentration was studied in order to compare the impact of climate changes with the impact of changes determined by anthropogenic emission.

New sensor based on membranes with magnetic nano-inclusions for early diagnosis in periodontal disease

A series of sodium selective membranes with magnetic nano-inclusions using p-tertbutyl calix[4]arene as ionophore and polymeric matrix (polyvinyl chloride) have been developed, and the corresponding sodium selective sensors were obtained for the first time. A linear range was registered between 3.1 × 10^-5 and 10^-1moldm^-3 and near Nernstian electrochemical answer: 55.73mV/decade has been recoreded for PVC (polyvinyl chloride) - based sodium selective sensor, with a response time of 45s. Due to their small dimensions, sensors could be used for measuring ions from the gingival crevicular fluid directly into the peri-odontal pocket, avoiding the difficulties of collecting an appropriate amount of fluid for analysis. Alterations in the inorganic ions level could be evidenced with this new device, assisting the early diagnosis and prevention of periodontal disease.

Chemical characteristics and source analysis on ionic composition of rainwater collected in the Carpathians "Cold Pole," Ciuc basin, Eastern Carpathians, Romania

A study of precipitation chemistry was conducted for 11 years (01 January 2006-31 December 2016) in the Ciuc basin, Eastern Carpathians, Romania. The studied area is an enclosed basin, also called "the Carpathians cold pole." All collected samples were analyzed for major cations and anions. HCO₃^- concentrations were calculated based on the empirical relationship between pH and HCO₃^-. The multiannual arithmetic mean of pH values was found to be 6.57. The lowest and highest pH values were measured in 2009 and 2013, being 6.57% lower, respectively, 7.57% higher than the multiannual mean. Only 3.31% of the studied rainwater samples indicate acidic character. In descending order, the majority of the samples are as follows: NH₄⁺ >Ca²⁺ >SO₄^2- >Cl^- >HCO₃^- >NO₃^- >Na⁺ >K⁺ >Mg²⁺ >NO₂^- >H⁺. Principal component analysis (PCA) showed the NH₄⁺, Ca²⁺, and Mg²⁺ contribution to the neutralization process and their sources. The anthropogenic origin of SO₄^2- was supported by the high non-sea-salt fraction (NSSF) (~ 91%). The results of this study suggest that rainwater chemistry is strongly influenced by local natural and anthropogenic sources (agricultural activities) rather than marine sources. The pollutants in rainwater samples were mainly derived from calcareous and dolomitic soil dust and specific local climatic conditions, long-range transport, local industry, and traffic sources.

Iono-molecular Separation with Composite Membranes II. Preparation and characterization of polysulphone and composite nanoparticles

This paper illustrates the possibility of producing iono-molecular separations using ionic colloidal ultrafiltration membrane of polysulfone synthetic solutions of cupric ions and nitro phenols through ultrafiltration assisted by polymeric nanoparticle composites based on polysulfone. In the present work, in order to reduce the operating pressure and increase the flow of water we are using the process of ultrafiltration through a polysulfone membrane in N-methylpyrrolidone 10% prepared by coagulation in isopropanol. The nanoparticles needed in colloidal ultrafiltration had been obtained through the immersion technique of precipitation of a solution of 5% PSf in N-methyl pyrrolidone containing 3% aniline in lower alcohols: methanol, ethanol, and isopropanol, followed by the oxidation of the remaining aniline in a solution of 10% hydrochloric acid and ammonium persulfate. The Nanoparticles of polysulfone (NP-PSf) and The three obtained variants of nanoparticles composites (NP-PSf-PANI) were morphologically (SEM) and (AFM), structurally and compositionally (FTIR) characterized and the results show that nanoparticles polysulfone have a much lower range than the composites. The Possibility of copper complexation by both nitrophenols, and by nanoparticle surface probably lead to the formation of more stable aggregates in the supply, which can sufficiently justify the increased retention. The Retentions of the chemical species in question use in all the tests made the same series:R NP-PSf-PANI-M] R NP-PSf-PANI-E] R NP-PSf-PANI-P] R NP-PSf

Poly(methyl methacrylate) with TiO2 nanoparticles inclusion for stereolitographic complete denture manufacturing - the fututre in dental care for elderly edentulous patients?

OBJECTIVES

The aim of this study was to obtain a Poly(methylmethacrylate) (PMMA)-TiO₂ nanocomposite material with improved antibacterial characteristics, suitable for manufacturing 3D printed dental prosthesis.

METHODS

0.2, 0.4, 0.6, 1, 2.5 by weight% of TiO₂ nanoparticles have been added to the commercially available stereolithographic PMMA material and the obtained nanocomposites have been analyzed using FTIR, SEM and also tested for antimicrobial efficacy against bacterial cultures from Candida species (C. scotti).

RESULTS

SEM images and EDX results highlighted the presence of TiO₂ in PMMA nanocomposites. The elemental composition (EDX) also showed the presence of other fillers included in stereolithographic PMMA solution. FTIR analysis clearly revealed changes in polymeric matrix structure when adding TiO₂ nanoparticles. Sample containing 0.4, 1 and 2.5wt% TiO₂ nanoparticles inhibited the growth of Candida scotti strain in standard conditions according to the toxicity control method (DHA). Increasing quantity of nano-titania has resulted in particles fooling, forming new aggregates instead of the homogenous dispersion of nanoparticles with modified viscosity characteristics and expected lower mechanical parameters.

CONCLUSIONS

Significant improvements in polymer characteristics and nice dispersion of the TiO₂ nanoparticles have been noticed for 0.4wt%, therefore it was used for stereolitographic complete denture prototyping.

CLINICAL SIGNIFICANCE

Incorporation of TiO₂ nanoparticles in PMMA polymer matrix was proved to have antibacterial effects, specifically on Candida species. The newly obtained 0.4% nanocomposite was successfully used with stereolitographic technique for complete denture manufacturing. However, mechanical and biocompatibility tests need to be performed in order to extend the clinical usage.

Aqueous Phase Biosorption of Pb(II), Cu(II), and Cd(II) onto Cabbage Leaves Powder

In this study, the biosorption of lead (Pb(II)), copper (Cu(II)), and cadmium (Cd(II)) ions from aqueous solution using waste of cabbage leaves powder (CLP) was investigated as a function of pH, shaking time, initial metal concentration, and biosorbent dose. The maximum removal efficiency at optimum condition in single biosorption system was 95.67, 92.42, and 88.92 % for Pb(II), Cu(II), and Cd(II) ions, respectively. These values reduced in ternary systems in the same sequence. Langmuir and extended Langmuir isotherm models were found to be the best fit of the isotherm data for single and ternary biosorption systems, respectively. The kinetic data of the three metals were better fit by the pseudo-second-order model with higher coefficient of determination and more closely predicted uptake. In addition, the results showed that the intraparticle diffusion was the dominating mechanism. Thermodynamic study showed that the biosorption of Pb(II), Cu(II), and Cd(II) onto CLP was a chemical reaction which was exothermic in nature. Finally, SEM image shows that CLP has a number of heterogeneous small pores while the Fourier transform infrared (FTIR) spectroscopic analysis showed that the carboxyl, amine, and hydroxyl groups are the major groups that are responsible for the biosorption process.