Novel Mesoporous Organosilicas with Task Ionic Liquids: Properties and High Adsorption Performance for Pb(II).

Removal of toxic contaminants such as Pb(II) from waste solutions is environmentally requested. Therefore, in this paper, for potential novel sorbents, mesoporous ionic liquid-functionalized silicas were synthesized and tested for the removal of Pb(II) from aqueous solutions. The successful synthesis of the adsorbents was proved by nuclear magnetic resonance (29Si and 13C NMR), Fourier transform infrared spectroscopy (FTIR), and elemental analysis. The structural and textural properties were determined using scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (TEM), and low-temperature N2 sorption, and the result showed that the applied procedure made it possible to obtain highly ordered particles with a two-dimensional mesostructure. The effects of several parameters including initial pH, contact time, adsorption temperature, and Pb(II) concentration were studied in detail and were discussed to evaluate the adsorption properties of the fabricated materials towards Pb(II). The obtained results confirmed a very high potential of the sorbents; however, the adsorption properties depend on the structure and amounts of the functional group onto fabricated materials. The sample ILS-Ox3-40 showed fast kinetics (equilibrium reached within 10 min) and capacity of 172 mg/g, and that makes it a promising sorbent for the cleanup of water contaminated by lead. It was also indicated that, regardless on structure of the tested materials, the Pb(II) removal was spontaneous and exothermic. The fabricated mesoporous silicas exhibited that they were easy to regenerate and had excellent reusability.

Antimicrobial Activity and Barrier Properties against UV Radiation of Alkaline and Enzymatically Treated Linen Woven Fabrics Coated with Inorganic Hybrid Material.

One of the directions of development in the textiles industry is the search for new technologies for producing modern multifunctional products. New solutions are sought to obtain materials that will protect humans against the harmful effects of the environment, including such factors as the activity of microorganisms and UV radiation. Products made of natural cellulose fibers are often used. In the case of this type of material, it is very important to perform appropriate pretreatment before subsequent technological processes. This treatment has the aim of removing impurities from the surface of the fibers, which results in the improvement of sorption properties and adhesion, leading directly to the better penetration of dyes and chemical modifiers into the structure of the materials. In this work, linen fabrics were subjected to a new, innovative treatment being a combination of bio-pretreatment using laccase from Cerrena unicolor and modification with CuO-SiO2 hybrid oxide microparticles by a dip-coating method. To compare the effect of alkaline or enzymatic pretreatment on the microstructure of the linen woven fabrics, SEM analysis was performed. The new textile products obtained after this combined process exhibit very good antimicrobial activity against Candida albicans, significant antibacterial activity against the Gram-negative Escherichia coli and the Gram-positive Staphylococcus aureus, as well as very good UV protection properties (ultraviolet protection factor (UPF) > 40). These innovative materials can be used especially for clothing or outdoor textiles for which resistance to microorganisms is required, as well as to protect people who are exposed to long-term, harmful effects of UV radiation.

Analysis of proteinuria in experimental model of ascending acute kidney injury.

Proteinuria accompanies kidney diseases of various etiology and correlates with the degree of organ damage. Analysis of proteinuria allows the location of pathophysiological process in the kidney, and assessment of the severity of the kidney disease in chronic and acute kidney injury (AKI). Ascending bacterial acute kidney injury develops as a consequence of pyelonephritis. It is a rare complication in patients with anatomical or functional dysfunctions of the urinary tract. AIM: The aim of the study was to perform the laboratory analysis of proteinuria in bacterial ascending AKI in an experimental model. MATERIALS AND METHODS: Female Wistar rats (n = 24) were intravesically administrated bacterial suspension of Escherichia coli (E. coli) to induce: pyelonephritis (group 1, 105 CFU/ml); AKI (group 2, 107 CFU/ml); AKI and urosepsis (group 3, 109 CFU/ml) respectively. Bacterial strain - E.coli, was isolated from a patient with acute pyelonephritis. The daily diuresis and urine protein excretion was measured the following days: 0, 7, 14 and 21. Moreover, electrophoretic separation of urine protein, densitometric analysis of albumin fraction and uromodulin concentration in urine were performed. Moreover, the key parameters for the diagnosis of AKI were assayed. RESULTS: Increased urinary protein excretion was observed in each of the study groups. Moreover, the study groups showed significant changes in protein selectivity in the urine. CONCLUSIONS: Moderately severe proteinuria was revealed while its selectivity suggested significant damage of glomeruli and renal tubules in groups with complications caused by AKI induced by ascending pyelonephritis.

Experimental gender related obesity effect of diet.

INTRODUCTION: High-calorie diet is responsible for excessive weight gain. Obesity has recently become world epidemics, affecting not only adults but also children, which makes it the biggest health problem in the world. Yet the underlying mechanism remains a matter of debate. OBJECTIVES: The aim of this study is to clarify the role of gender in high fat diet induced obesity in pups and adult animals. MATERIALS AND METHODS: Female rats were fed low/ high fat diet during mating, pregnancy and lactation. The offspring and adult rats fed different diet had their body weight and temperature measurements taken twice a week. On the 21st day of the experiment the animals underwent anesthesia in order to have their blood samples collected for lipid profile. RESULTS: After 3 weeks on HF diet female pups body weight was higher than in control group (p 〈0.05). Contrary to the female pups, the increase in body weight was higher (p 〈0.05) in male pups and occurred after 2 and 3 weeks. In adult female rats body weight increased after 2 weeks on HF, while in adult male group such weight gain was observed no sooner than after 3 weeks. A er three weeks of the experiment body weight was correlated positively (r = 0.941) with lipid profile of adult both gender groups on HF diet. CONCLUSIONS: In male pups group body weight increased faster and achieved higher values then in female pups. On the contrary, in adult group of females body weight increased faster than in male rats and achieved similar values.

Spectral heart rate variability in rats with cyclophosphamide-induced hemorrhagic cystitis treated with cyclooxygenase inhibitors.

The pathogenesis of cyclophosphamide-induced hemorrhagic cystitis (CP-HC) is complex, involving the im- pact of many systemically and locally released agents on autonomic nervous system (ANS) activity, that affects bladder functioning. The purpose of our study was to provide an indirect evaluation of ANS functional status in experimental CP-HC model, involving prostaglandin synthesis block resulting from administration of cyclooxygenase inhibitors. The ANS activity was estimated through the spectral analysis of heart rate variability (HRV) in CP-HC rats divided into three study groups: 1-control, 2-treated with meloxicam (MLX) that preferentially blocks COX-2, and 3-treated with piroxicam (PRX) that inhibits COX1 and 2 activity. In animals treated either with MLX or PRX, the percent distribution of the spectrum in relation to components of very low (VLF) and low (LF) frequency was not different from the control group. PRX-treated group displayed nearly two times lower percent share of the high frequency (HF) component compared to the control. Moreover, an increase of the normalized LF (nLF) value with simultaneous reduction of the normalized HF (nHF) value were noted in PRX-treated rat with no change of these parameters for MLX-treated rats. The HRV analysis in CP-HC rats receiving PRX, indicated a functional reorganization manifested by reduced parasym- pathetic activity and increased sympathetic tonus. A partial prostaglandin synthesis block caused by COX-2 inhibitor (meloxicam) caused no significant changes of evaluated HRV parameters compared to the control. Assessing functional changes of the ANS caused by prostaglandin synthesis block it should be stated that prostaglandins synthesized by the constitutive COX-1 isoform seem to maintain the parasympathetic activity, which may be associated with the cholinergic anti-inflammatory pathway and resolution of inflammation in course of cyclophosphamide-induced cystitis.

The Influence of the Modification of Carbon Nanotubes on the Properties of Copper Matrix Sintered Materials.

This paper presents the results of research on the microstructure, mechanical, and tribological properties of Cu/0.5 wt.% MWCNT (multi-walled carbon nanotube) sintered composite materials produced by powder metallurgy. The purpose of this research was to investigate the impact of carbon nanotube modifications on the uniformity of their dispersion and the effectiveness of their bonding with the matrix. The MWCNTs were modified by chemical oxidation. Additionally, a modification of the ingredient mixing method utilizing ultrasonic frequencies was employed. The tests were carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Vickers hardness tests, static compression tests, and wear tests using the pin-on-disc method. Furthermore, mechanical properties and strain distribution analyses of the micro-specimens were conducted using the Micro-Fatigue System (MFS). The implemented modifications had a positive effect on the dispersion of MWCNTs in the copper matrix and on the mechanical and tribological properties of the sinters.

New Insights into the Application of Biocompatible (Un)Modified TiO2 and TiO2-ZrO2 Oxide Fillers in Light-Curing Materials.

A novel UV-light-curable poly(ethylene glycol) diacrylate matrix composite material with unmodified and methacryloxyl-grafted TiO2 and TiO2-ZrO2 systems was developed and tested as a potential coating material for medical components. The main goal of the research was to evaluate how the addition of (un)modified inorganic oxide fillers affects the properties of the composition (viscosity, UV/Vis spectra), the kinetics of photocuring (photo-DSC), and the morphological (SEM), physicochemical, and thermal properties (DSC, TGA) of the resulting composites. The applied filler functionalization process decreased their polarity and changed their size, BET surface area, and pore volume, which influenced the viscosity and kinetics of the photocurable system. In addition, the addition of synthesized fillers reduced the polymer's glass transition temperature and increased its thermal stability. It was also observed that additional UV irradiation of the tested composite changed its surface, resulting in hydrophobic properties (with the addition of 7 wt.% filler, an increase in the contact angle by more than 45% was observed).

[Neural control disturbances of the gastrointestinal tract and visceral pain in inflammatory bowel diseases]. / Zaburzenia kontroli nerwowej przewodu pokarmowego i ból trzewny w nieswoistych chorobach zapalnych jelits.

Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition, the etiology of which is composed of factors such as the environment, genetic predisposition, gut dysbiosis and inadequate immune response. The pathologic findings in Crohn's disease and ulcerative colitis are related to dysfunction of gastrointestinal secretion and motility and also disturbed visceral sensory function, with accompanying intestinal and parenteral complications. The systemic inflammatory response affects neurological control via the gut-brain axis, which modulates the cooperation of the autonomic nervous system (ANS), enteric nervous system (ENS) and gut-associated lymphoid tissue (GALT). In chronic inflammation the intestinal neuropathy disrupts peristalsis and intestinal secretion as well as causing unpleasant symptoms of the patients. Pain receptors are stimulated by inflammatory mediators, and due to the intensified activation of the nociceptive system visceral hypersensitivity through central and peripheral sensitization is generated. Chronic visceral pain negatively influences the course of disease and the quality of the patient's life. The growing knowledge about the neurological control dysfunction of the intestine and immune system dysregulation could provide proper directives for treatment of inflammatory bowel diseases.

The changes of heart rate variability in response to deep breathing in professional swimmers.

INTRODUCTION: The analysis of heart rate variability (HRV) is a useful tool for the evaluation of adaptation processes of autonomic nervous system (ANS) to physical exercise. The deep breathing test (DB) induces the increased activity of the parasympathetic component of ANS. The aim of the study was to evaluate the influence of DB on ANS activity in professional swimmers and non-trained persons. METHODS: The study included 10 healthy swimmers (5 women and 5 men, mean age 21 ± 2 yrs) in the transitory phase of their training cycle, and a control group comprising 31 healthy volunteers. The evaluation of ANS activity was based on the time and frequency domain indices of HRV determined at rest and during DB. RESULTS: Compared to the controls, swimmers were characterized by significantly higher values of the following HRV indices determined at rest: mRR (902.9 ± 102.5 ms vs. 744 ± 67.5 ms, p <0.05), rMSSD (71.4 ± 46.9 ms vs. 41.3 ± 20.7 ms, p <0.05), pNN50 (28.3 ± 17.4% vs.14 ± 10.7%, p <0.05), LF (603.5 ± 208.2 ms2 vs. 445.2 ± 137 ms2, p <0.03). Also during DB test, the values of the following HRV indices of the swimmers were significantly higher than in the controls: mRR (899.2 ± 69.2 ms vs. 766.4 ± 63.6 ms, p <0.05), SDNN (114.1 ± 45.1 ms vs. 79 ± 27.7 ms, p <0.05), rMSDD (81.9 ± 38.2 ms vs. 50.7 ± 27 ms, p <0.05), pNN50 (32.9 ± 14.3 % vs. 20.6 ± 14.6%, p <0.05), TP (1972.7 ± 809.5 ms2 vs. 1329.7 ± 532 ms2, p <0.05), HF (657.1 ± 330.9 ms2 vs. 405.7 ± 217 ms2, p <0.05), LF (753.3 ± 294 ms2 vs. 533 ± 213.4 ms2, p <0.05). The analysis of value relative DB-induced changes in time and frequency domain HRV indices revealed significant intergroup differences in reaction to parasympathetic stimulation. CONCLUSIONS: Based on the results presented in this study, the swimmers' response to deep breathing seems stronger than in persons without professional training. The deep breathing test may be a useful tool to evaluate the dynamic changes in the parasympathetic activity of ANS of sportspersons.

Postprandial effect of gastrointestinal hormones and gastric activity in patients with irritable bowel syndrome.

Altered gut regulation, including motor and secretory mechanisms, is characteristic of irritable bowel syndrome (IBS). The severity of postprandial symptoms in IBS patients is associated with discomfort and pain; gas-related symptoms such as bloating and abdominal distension; and abnormal colonic motility. The aim of this study was to assess the postprandial response, i.e., gut peptide secretion and gastric myoelectric activity, in patients with constipation-predominant IBS. The study was conducted on 42 IBS patients (14 males, 28 females, mean age 45.1 ± 15.3 years) and 42 healthy participants (16 males, 26 females, mean age 41.1 ± 8.7 years). The study assessed plasma gut peptide levels (gastrin, CCK-Cholecystokinin, VIP-Vasoactive Intestinal Peptide, ghrelin, insulin) and gastric myoelectric activity obtained from electrogastrography (EGG) in the preprandial and postprandial period (meal-oral nutritional supplement 300 kcal/300 ml). Mean preprandial gastrin and insulin levels were significantly elevated in IBS patients compared to the control group (gastrin: 72.27 ± 26.89 vs. 12.27 ± 4.91 pg/ml; p < 0.00001 and insulin: 15.31 ± 12.92 vs. 8.04 ± 3.21 IU/ml; p = 0.0001), while VIP and ghrelin levels were decreased in IBS patients (VIP: 6.69 ± 4.68 vs. 27.26 ± 21.51 ng/ml; p = 0.0001 and ghrelin: 176.01 ± 88.47 vs. 250.24 ± 84.55 pg/ml; p < 0.0001). A nonsignificant change in the CCK level was observed. IBS patients showed significant changes in postprandial hormone levels compared to the preprandial state-specifically, there were increases in gastrin (p = 0.000), CCK (p < 0.0001), VIP (p < 0.0001), ghrelin (p = 0.000) and insulin (p < 0.0001). Patients with IBS showed reduced preprandial and postprandial normogastria (59.8 ± 22.0 vs. 66.3 ± 20.2%) compared to control values (83.19 ± 16.7%; p < 0.0001 vs. 86.1 ± 9.4%; p < 0.0001). In response to the meal, we did not observe an increase in the percentage of normogastria or the average percentage slow-wave coupling (APSWC) in IBS patients. The postprandial to preprandial power ratio (PR) indicates alterations in gastric contractions; in controls, PR = 2.7, whereas in IBS patients, PR = 1.7, which was significantly lower (p = 0.00009). This ratio reflects a decrease in gastric contractility. Disturbances in the postprandial concentration of gut peptides (gastrin, insulin and ghrelin) in plasma may contribute to abnormal gastric function and consequently intestinal motility, which are manifested in the intensification of clinical symptoms, such as visceral hypersensitivity or irregular bowel movements in IBS patients.

Synthesis and Surface Properties of Piperidinium-Based Herbicidal Ionic Liquids as a Potential Tool for Weed Control.

A series of piperidinium-based herbicidal ionic liquids (HILs) were synthesized and investigated. The designed HILs, obtained with high yields, consisted of cation 1-alkyl-1-methylpiperidinium with surface activity and a commercially available herbicidal anion: (3,6-dichloro-2-methoxy)benzoates (dicamba). The above-mentioned compounds were characterized in terms of surface activity and phytotoxicity. Preliminary results were obtained at higher wettability for all HILs when compared to the wettability of commercial Dicash, with HIL having 18 atoms in the carbon chain being the best effectiveness in wetting surfaces (weeds and crop leaves), whereby a drop of HILs with short alkyl chains (C8-C10) could not slide down a leaf. Our findings present that wettability or mobility of HILs drops varied depending on the plant species. Moreover, in this study, by zeta potential and atomic force microscopy measurements, we provide conclusive evidence to demonstrate that alkyl chain elongation plays a significant role in the evolution of surface properties of HILs.

Sorption of ionic liquids in soil enriched with polystyrene microplastic reveals independent behavior of cations and anions.

Recently, much attention has been focused on the application of the Ionic Liquids (ILs) with herbicidal activity in agriculture. It has been suggested that through the appropriate selection of cations and anions, one can adjust the properties of ILs, particularly the hydrophobicity, solubility, bioavailability, toxicity. In practical agricultural conditions, it will be beneficial to reduce the mobility of herbicidal anions, such as the commonly applied 2,4-dichlorophenoxyacetic acid [2,4-D] in the soil. Furthermore, microplastics are becoming increasingly prevalent in the soil, potentially stimulating herbicidal sorption. Therefore, we investigated whether cations in ILs influence the mobility of anions in OECD soil supplemented with polystyrene microplastic (PS). For this purpose, we used the 2,4-D based ILs consisting of: a hydrophilic choline cation [Chol][2,4-D] and a hydrophobic choline cation with a C12chain [C12Chol][2,4-D]. Characterization of selected micropolystyrene was carried out using the BET sorption-desorption isotherm, particle size distribution and changes in soil sorption parameters such as soil sorption capacity and cation exchange capacity. Based on the batch sorption experiment, the effect of microplastic on the sorption of individual cations and anions in soil contaminated with micropolystyrene was evaluated. The results obtained indicate that the introduction of a 1-10% (w/w) PS resulted in an 18-23% increase of the soil sorption capacity. However, the sorption of both ILs' cations increased only by 3-5%. No sorption of the [2,4-D] anion was noted. This suggests that cations and anions forming ILs, behave independently of each other in the environment. The results indicate the fact that ILs upon introduction into the environment are not a new type of emerging contaminant, but rather a typical mixture of ions. It is worth noting that when analyzing the behavior of ILs in the environment, it is necessary to follow the fate of both cations and anions.

Experimental Investigation of the Failure Scenario of Various Connection Types between Thin-Walled Beam and Sandwich Panel.

The paper presents failure scenarios for various types of connections between a thin-walled beam and a sandwich panel. In addition to standard connections used in civil engineering applications, that is, self-drilling fasteners for sandwich panels, the study examined the use of bolts, blind rivets, and double-sided acrylic tape applied linearly and pointwise. The connections were subjected to the horizontal load applied with constant eccentricity with respect to the plane of the connection surface. This load arrangement simulates the behaviour of a free flange of the thin-walled beam in bending while lateral-torsional buckling occurs. In this way, the research covers the determination of the lateral stiffness of the thin-walled beam-free flange, while the other flange is connected to the sandwich panel using various connection systems.

[Electric activity of vagus nerve in rats according to satiety]. / Aktywnosc elektryczna nerwu blednego u szczurów w zaleznosci od stopnia sytosci.

Vagus nerve as a part of brain-gut axis transmits peripheral information to the brain via vagovagal reflexes. Electric properties of the vagus are not exactly known. Analysis of electric changes in vagal nerves evoked by physiologic impulse such as stomach distention by food would facilitate applying better documented and therefore safer vagal neuromodulation. The aim of our study was analysis and interpretation of electric properties of the left vagus in vivo in fasted and satiated Wistar rats. Silver measuring electrodes connected to analog amplifier (A-M Systems 3000) were attached to the nerve in the neck region. The signal was filtered and probing by computer recording system (ADInstruments Power Lab) and additional analyses were performed using GNU Octave programme. Our resuts have shown that the higher amplitude the smaller number of counted impulses in the vagus was detected. This relationship was true only till the maximum level typical for each recording (about 15-20 dB). We note that observed inter spike interval can be approximated with log-normal distribution, and that its mu parameter is enough to characterize a particular recording. Satiated rats were characterized by higher number of spikes per second in the nerve than fasted ones (0.9 vs 0.26) indicating that food intake increased nervous activity 3-4 times comparing to fasted state. The outcomes encourage us to state that good quality characteristic of the left vagus nerve activity provides an effective tool for detection of peripheral signals which are transmitting via vagal afferents to the higher centres. Target vagal neuromodulation to obtain certain terapeutic effects may be possible.

Catalytic and Physicochemical Evaluation of a TiO2/ZnO/Laccase Biocatalytic System: Application in the Decolorization of Azo and Anthraquinone Dyes.

A TiO2/ZnO oxide system was proposed as a support for the immobilization of laccase from Trametes versicolor (LTV). The obtained TiO2/ZnO/LTV biocatalytic system was then applied in the decolorization/degradation of C.I. Reactive Black 5 and C.I. Acid Green 25 dyes. The efficiency of immobilization was evaluated based on catalytic properties (Bradford method, oxidation reaction of 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and physicochemical (spectroscopic, porous, electrokinetic) analysis. The immobilization process was carried out with high performance (99.4%). Immobilized laccase retained about 40% of its activity in the whole analyzed temperature range and after 10 reaction cycles. Immobilization efficiency was also indirectly confirmed by the presence of characteristic functional groups (-C-H and -C-O), nitrogen and carbon on the TiO2/ZnO/LTV biocatalytic surface, identified by spectroscopic analyses. The increase in the surface area to 126 m2/g, change of isoelectric point (2.0) and zeta potential ranges (from +12.0 to -20.0 mV) after the immobilization process were also observed. The results show that the designed biocatalytic system enables the removal of acid dyes (C.I. Reactive Black 5 and C.I. Acid Green 25) with high efficiency (99% and 70%, respectively). Mass spectroscopy analysis indicated possible degradation products formed by the cleavage of N=N and C-N bonds.

The TiO2-ZnO Systems with Multifunctional Applications in Photoactive Processes-Efficient Photocatalyst under UV-LED Light and Electrode Materials in DSSCs.

The main goal of the study was the hydrothermal-assisted synthesis of TiO2-ZnO systems and their subsequent use in photoactive processes. Additionally, an important objective was to propose a method for synthesizing TiO2-ZnO systems enabling the control of crystallinity and morphology through epitaxial growth of ZnO nanowires. Based on the results of X-ray diffraction analysis, in the case of materials containing a small addition of ZnO (≥5 wt.%), no crystalline phase of wurtzite was observed, proving that a high amount of modified titanium dioxide can inhibit the crystallization of ZnO. The transmission electron microscopy (TEM) results confirmed the formation of ZnO nanowires for systems containing ≥ 5% ZnO. Moreover, for the synthesized systems, there were no significant changes in the band gap energy. One of the primary purposes of this study was to test the TiO2-ZnO system in the photodegradation process of 4-chlorophenol using low-power UV-LED lamps. The results of photo-oxidation studies showed that the obtained binary systems exhibit good photodegradation and mineralization efficiency. Additionally, it was also pointed out that the dye-sensitized solar cells can be a second application for the synthesized TiO2-ZnO binary systems.

Modification of structured bio­carbon derived from spongin-based scaffolds with nickel compounds to produce a functional catalyst for reduction and oxidation reactions: Potential for use in environmental protection.

Three different 3D fibrous-like NiO/Ni(OH)2/Ni­carbonized spongin-based materials were prepared via a simple sorption-reduction method. Depending on the support used, the catalysts were composed of carbon, nickel oxide, nickel hydroxide and zero-valent nickel, with the surface content of the nickel-containing phase in the range 15.2-26.0 wt%. Catalytic studies showed promising activity in the oxidation of phenolic compounds in water and in the reduction of 4-nitrophenol. The oxidation efficiency depends on the substrate used and ranges from 80% for phenol at pH 2 to 99% for 4-chlorophenoxyacetic acid (4-CPA) and methylchlorophenoxypropionic acid (MCPP). In the reduction reaction, all catalysts exhibited superior activity, with rate constants in the range 0.648-1.022 min-1. The work also includes a detailed investigation of reusability and kinetic studies.

Synthesis of Selected Mixed Oxide Materials with Tailored Photocatalytic Activity in the Degradation of Tetracycline.

The elimination of antibiotics occurring in the natural environment has become a great challenge in recent years. Among other techniques, the photocatalytic degradation of this type of pollutant seems to be a promising approach. Thus, the search for new photoactive materials is currently of great importance. The present study concerns the sol-gel synthesis of mono, binary and ternary TiO2-based materials, which are used as active photocatalysts. The main goal was to evaluate how the addition of selected components-zirconium dioxide (ZrO2) and/or zinc oxide (ZnO)-during the synthesis of TiO2-based materials and the temperature of thermal treatment affect the materials' physicochemical and photocatalytic properties. The fabricated mixed oxide materials underwent detailed physicochemical analysis, utilizing scanning-electron microscopy (SEM), X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), energy-dispersive X-ray spectroscopy (EDS), low-temperature N2 sorption (BET model), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The synthesized mixed oxide materials were used as photocatalysts in the heterogeneous photodegradation of tetracycline (TC). The physicochemical properties of the fabricated photocatalysts, including morphology, crystalline and textural structure, as well as the pH of the reaction system in the photocatalytic tests, were taken into account in determining their photo-oxidation activity. LC-MS/MS analysis was used to identify the possible degradation products of the selected antibiotic.

Evaluation of the physico-chemical properties of hydrocarbons-exposed bacterial biomass.

In the efforts for the removal of hazardous materials from the environment biological processes are a valuable tool. Although much attention has been paid to the changes in bacteria at the omics level, another, physical-chemical perspective on the issue is essential, as little is known of microbial response to continuous exposition on harmful substances. This study provides in-depth characterization of the physical-chemical parameters of bacterial biomass after hydrocarbons exposure. To provide comparability of the harmful effects of chlorotoluenes and xylenes non-exposed and 12-months hydrocarbons exposed cells were analyzed, using the advanced spectrometric methods, inverse gas chromatography and low-temperature N2 sorption to evaluate acid-base as well as dispersive properties of the studied biomass. Presented results indicate P. fluorescens B01 cells strategy aimed at protecting the cell, thus lowering its' biodegradation efficiency as a result of metabolic stress. The outcome of the study was that prolonged exposure to pollutants might reduce the bioavailability of hydrocarbons to bacteria cells, and consequently decrease the effectiveness of decontamination of polluted sites by indigenous microorganisms.

Hydrothermally Assisted Fabrication of TiO2-Fe3O4 Composite Materials and Their Antibacterial Activity.

The TiO2-Fe3O4 composite materials were fabricated via the hydrothermal-assisted technique. It was determined how the molar ratio of TiO2 to Fe3O4 influences the crystalline structure and morphology of the synthesized composite materials. The effect of the molar ratio of components on the antibacterial activity was also analyzed. On the basis of XRD patterns for the obtained titanium(IV) oxide-iron(II, III) oxide composites, the two separate crystalline forms-anatase and magnetite -were observed. Transmission electron microscopy revealed particles of cubic and tetragonal shape for TiO2 and spherical for Fe3O4. The results of low-temperature nitrogen sorption analysis indicated that an increase in the iron(II, III) oxide content leads to a decrease in the BET surface area. Moreover, the superparamagnetic properties of titanium(IV) oxide-iron(II, III) oxide composites should be noted. An important aim of the work was to determine the antibacterial activity of selected TiO2-Fe3O4 materials. For this purpose, two representative strains of bacteria, the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, were used. The titanium(IV) oxide-iron(II, III) oxide composites demonstrated a large zone of growth inhibition for both Gram-positive and Gram-negative bacteria. Moreover, it was found that the analyzed materials can be reused as antibacterial agents in three consecutive cycles with good results.