Coating of Filter Materials with CeO2 Nanoparticles Using a Combination of Aerodynamic Spraying and Suction

Textiles and nonwovens (including those used in ventilation systems as filters) are currently one of the main sources of patient cross-infection. Healthcare-associated infections (HAIs) affect 5-10% of patients and stand as the tenth leading cause of death. Therefore, the development of new methods for creating functional nanostructured coatings with antibacterial and antiviral properties on the surfaces of textiles and nonwoven materials is crucial for modern medicine. Antimicrobial filter technology must be high-speed, low-energy and safe if its commercialization and mass adoption are to be successful. Cerium oxide nanoparticles can act as active components in these coatings due to their high antibacterial activity and low toxicity. This paper focuses on the elaboration of a high-throughput and resource-saving method for the deposition of cerium oxide nanoparticles onto nonwoven fibrous material for use in air-conditioning filters. The proposed spraying technique is based on the use of an aerodynamic emitter and simultaneous suction. Cerium oxide nanoparticles have successfully been deposited onto the filter materials used in air conditioning systems; the antibacterial activity of the ceria-modified filters exceeded 4.0.

Simultaneous hydrodynamic cavitation and glow plasma discharge for the degradation of metronidazole in drinking water

In this study, a novel hydrodynamic cavitation unit combined with a glow plasma discharge system (HC-GPD) was proposed for the degradation of pharmaceutical compounds in drinking water. Metronidazole (MNZ), a commonly used broad-spectrum antibiotic, was selected to demonstrate the potential of the proposed system. Cavitation bubbles generated by hydrodynamic cavitation (HC) can provide a pathway for charge conduction during glow plasma discharge (GPD). The synergistic effect between HC and GPD promotes the production of hydroxyl radicals, emission of UV light, and shock waves for MNZ degradation. Sonochemical dosimetry provided information on the enhanced formation of hydroxyl radicals during glow plasma discharge compared to hydrodynamic cavitation alone. Experimental results showed a MNZ degradation of 14% in 15 min for the HC alone (solution initially containing 300 × 10-6 mol L-1 MNZ). In experiments with the HC-GPD system, MNZ degradation of 90% in 15 min was detected. No significant differences were observed in MNZ degradation in acidic and alkaline solutions. MNZ degradation was also studied in the presence of inorganic anions. Experimental results showed that the system is suitable for the treatment of solutions with conductivity up to 1500 × 10-6 S cm-1. The results of sonochemical dosimetry showed the formation of oxidant species of 0.15 × 10-3 mol H2O2 L-1 in the HC system after 15 min. For the HC-GPD system, the concentration of oxidant species after 15 min reached 13 × 10-3 molH2O2L-1. Based on these results, the potential of combining HC and GPD systems for water treatment was demonstrated. The present work provided useful information on the synergistic effect between hydrodynamic cavitation and glow plasma discharge and their application for the degradation of antibiotics in drinking water.

Differences in the Differentiation Potential and Relative Levels of Gene Expression in the Bone Marrow-Derived Fibroblast Colony-Forming Units in Patients during the Onset of Aplastic Anemia Depending on the Disease Severity

The differentiation potential of individual clones of fibroblast CFU (CFU-F) was studied and the relative expression level of genes was analyzed in the culture of CFU-F from the bone marrow in patients with non-severe and severe forms of aplastic anemia at the onset of the disease. The differentiation potential of CFU-F clones was determined by the relative expression of marker genes using quantitative PCR. In aplastic anemia, the ratio of CFU-F clones with different differentiation potential changes, but the molecular mechanisms of this phenomenon are different in non-severe and severe aplastic anemia. In the culture of CFU-F in non-severe and severe aplastic anemia, the relative expression level of genes associated with the maintenance of the hematopoietic stem cell in the bone marrow niche changes, but the decrease in the expression of immunoregulatory genes occurs in severe form only, which may reflect differences in the pathogenesis of non-severe and severe aplastic anemia.

Sonochemical processes for the degradation of antibiotics in aqueous solutions: A review

Antibiotic residues in water are general health and environmental risks due to the antibiotic-resistance phenomenon. Sonication has been included among the advanced oxidation processes (AOPs) used to remove recalcitrant contaminants in aquatic environments. Sonochemical processes have shown substantial advantages, including cleanliness, safety, energy savings and either negligible or no secondary pollution. This review provides a wide overview of the different protocols and degradation mechanisms for antibiotics that either use sonication alone or in hybrid processes, such as sonication with catalysts, Fenton and Fenton-like processes, photolysis, ozonation, etc.

Flow-mode water treatment under simultaneous hydrodynamic cavitation and plasma

Over the last two decades, the scientific community and industry have made huge efforts to develop environmental protection technologies. In particular, the scarcity of drinking water has prompted the investigation of several physico-chemical treatments, and synergistic effects have been observed in hyphenated techniques. Herein, we report the first example of water treatment under simultaneous hydrodynamic cavitation and plasma discharge with the intense generation of radicals, UV light, shock waves and charged particles. This highly reactive environment is well suited to the bulk treatment of polluted water (i.e. E. coli disinfection and organic pollutant degradation). We have developed a new prototype and have efficiently applied this hybrid technology to water disinfection and the complete degradation of methanol in water with the aim of demonstrating its scalability. We have analyzed the mechanisms of water disinfection under the abovementioned conditions and verified them by measuring cavitation noise spectra and plasma emission spectra. We have also used the degradation of textile dyes and methanol solutions as an indicator for the formation of radicals.

[Immunosupressive therapy of aplastic anemia patients: successes and failures (single center experiment 2007-2016)]

Treatment programs for patients with acquired aplastic anemia include two main therapeutic options: allogeneic bone marrow transplantation and combined immunosuppressive therapy (IST). However, combined IST remains the method of choice for most adult AA patients. This study included 120 AA patients who received IST at the National Research Center for Hematology in 20072016. The analysis was applied to 120 patients. Median age was 25 (1765) years, M/F: 66/54, SAA/NSAA: 66%/34%. Effectiveness of IST was carried out in 120 patients with AA. This group did not include 8 SAA patients who died during the first 3 months from the start of treatment from severe infectious complications (early deaths 6.2%) and 2 AA patients who dropped out of surveillance. The observation time was 55 (6120) months. Paroxysmal nocturnal hemoglobinuria (PNH clone) was detected in 67% of AA patients. The median PNH clone size (granulocytes) was 2.5 (0.0199.5)%. The treatment was according to the classical protocol of combined IST: horse antithymocytic globulin and cyclosporin A. Most of patients (87%) responded to combined immunosuppressive therapy. To achieve a positive response, it was sufficient to conduct one course of ATG to 64% of patients, two courses of ATG 24% of patients and 2% of patients responded only after the third course of ATG. A positive response after the first course was obtained in 64% of patients included in the analysis. Most of the responding patients (93%) achieve a positive response after 36 months from the start of treatment. Therefore, the 3rd6th months after the first course of ATG in the absence of an answer to the first line of therapy can be considered the optimal time for the second course of ATG. This tactic allows to get an answer in another 58% of patients who did not respond to the first course of ATG. The probability of an overall 10-year survival rate was 90% (95% confidence interval 83.696.2).

The pecularities of ultrasonic equipment design for stabilization of dispersed structures of alumosilicic reagents for wastewater treatment

Acoustic fields formed during operation of ultrasonic reactors with waveguides of following types: rod-type, cylindrical with rectangular protrusions and tubular were calculated and measured. The influence of distribution of acoustic fields arising from the operation of waveguide systems of three different types on the efficiency of ultrasonic activation of alumosilicic flocculant-coagulant and magnetite intended for water purification was investigated. It was shown that regardless of the equipment used on an industrial scale it is possible to reactivate the alumosilicic flocculant-coagulant even after the shelf life period of it passed, however in case of activation of magnetite the use of a bigger reactor in inefficient. In case of industrial scale processes, the choice of the correct reactor design is of significant importance, since it allows to reduce the required processing time, and, as a result, the energy consumption of the processes. The advantages of tubular waveguide systems include the possibility of processing large volumes of liquid. The high efficiency and uniformity of the excited ultrasonic fields can lead to reduction of operating costs. In case of smaller flows, the waveguide system with rectangular protrusions allowed to obtain better results. Our work illustrates the dependence of the success of a specific method on the choice of the waveguide and the size of the reactor during upscale.

A sol-gel method for applying nanosized antibacterial particles to the surface of textile materials in an ultrasonic field

To prevent possible spread of nosocomial infections - HAI (Healthcare Acquired Infections) in healthcare facilities, Antibacterial textiles are developed. This carried out study has been conducted to assess the feasibility of the method of obtaining antibacterial coatings on textile materials. Specifically, the sol-gel method for synthesis of titanium dioxide nanoparticles in combination with zinc oxide nanoparticles from titanyl sulphate and zinc nitrate hexahydrate has been investigated. During the synthesis of titanium dioxide nanoparticles in combination with the zinc oxide nanoparticles, the coated textile material showed stable antibacterial properties with a suppression level ofEscherichia coliof more than 99.99%. The method has been tested on a semi-industrial scale in roll-to-roll experimentby applying homogenous coatings at a speed of 1,5 m per minute.

A method for water well regeneration based on shock waves and ultrasound

The regeneration of water wells is an urgent problem nowadays, when drilling of new wells becomes more and more expensive. Formation damage leads to a reduction of the formation's permeability and/or pore volume which in turn inhibits the ability of the water to flow from the reservoir formation into the wellbore. A new technology that uses high-power ultrasound to remove formation damage of water wells has been developed. The effectiveness of regeneration of wells can be enhanced if ultrasound and shockwaves are used during the same treatment. It was shown by computer modelling, that the two methods have different depths of impact. Whereas the ultrasonic method has a strong impact on the area of the filter tube, the impact of the shock waves is focused on the gavel pack, the wall of the well and the adjacent aquifer. A shockwave treatment, which is normally more effective due to larger impact zone, needs to be followed by ultrasonic treatment in order to facilitate the removal of the detached deposits. These theoretical assumptions were confirmed by field tests on two wells. The use of the method leaded to an increase of the production by 40% and 109% respectively.

Acoustic and sonochemical methods for altering the viscosity of oil during recovery and pipeline transportation

Reduction of oil viscosity is of great importance for the petroleum industry since it contributes a lot to the facilitation of pipeline transportation of oil. This study analyzes the capability of acoustic waves to decrease the viscosity of oil during its commercial production. Three types of equipment were tested: an ultrasonic emitter that is located directly in the well and affects oil during its production and two types of acoustic machines to be located at the wellhead and perform acoustic treatment after oil extraction: a setup for ultrasonic hydrodynamic treatment and a flow-through ultrasonic reactor. In our case, the two acoustic machines were rebuilt and tested in the laboratory. The viscosity of oil was measured before and after both types of acoustic treatment; and 2, 24 and 48h after ultrasonic treatment and 1 and 4h after hydrodynamic treatment in order to estimate the constancy of viscosity reduction. The viscosity reduction achieved by acoustic waves was compared to the viscosity reduction achieved by acoustic waves jointly with solvents. It was shown, that regardless of the form of powerful acoustic impact, a long lasting decrease in viscosity can be obtained only if sonochemical treatment is used. Using sonochemical treatment based on ultrasonic hydrodynamic treatment a viscosity reduction by 72,46% was achieved. However, the reduction in viscosity by 16%, which was demonstrated using the ultrasonic downhole tool in the well without addition of chemicals, is high enough to facilitate the production of viscous hydrocarbons.

[The dynamics of paroxysmal nocturnal hemoglobinuria clone in patients with aplastic anemia in process of immune suppressive therapy]

The implementation of principles of highly sensitive flow cytometry into diagnostic of paroxysmal nocturnal hemoglobinuria increased rate of detection of paroxysmal nocturnal hemoglobinuria clone in patients with aplastic anemia already at early stages of diagnosis establishment (up to 79%). However, detection of paroxysmal nocturnal hemoglobinuria clone attracts interest not only from point of view of progression in % of patients with aplastic anemia). The occurrence of paroxysmal nocturnal hemoglobinuria clone in patients with aplastic anemia can be accompanied by hidden disorders of haemopoesis with increasing risk in conditions of proliferative stress. Hence, it is necessary to monitor the given clone during all period of observation. The study is a prospective investigation analyzing dynamics of paroxysmal nocturnal hemoglobinuria clone in process of immune suppressive therapy applied to 44 patients with aplastic anemia. The mentioned clone was initially detected in 59.6% of patients. The median of observation amounted to 27 (9-48) months. Depending on size of granulocytic paroxysmal nocturnal hemoglobinuria clone patients were allocated in four conditional groups: group I - from 0.01% to 0.99% (n=11); group II - from 1% to 9.99% (n=8); group III - from10% to 49.9% (n=4); group IV - from 50% and more (n=5). In the course of study the differently directed dynamics of paroxysmal nocturnal hemoglobinuria clone was revealed. In 3 out of 11 patients from group I median of paroxysmal nocturnal hemoglobinuria clone increased from minor values (less than 1%) to 3.55%; at that in one patient occurred total elimination of paroxysmal nocturnal hemoglobinuria clone to 12th month of observation. The noticeable unidirectional dynamics was established in patients of group III: already to 3d month of observation, simultaneously with becoming of remission, median of size of paroxysmal nocturnal hemoglobinuria clone in group diminished from 22.9% (18.39%-24.77%) to 5.6% (1.5%-6.7%). Among patients of groups II and IV paroxysmal nocturnal hemoglobinuria clone remained stable. The development of hemolytic form of paroxysmal nocturnal hemoglobinuria was observed in all patients of group IV i.e. in 18% of patients with aplastic anemia with primarily detected paroxysmal nocturnal hemoglobinuria clone. In the process of observation, in 37% of patients with aplastic anemia without primarily detected paroxysmal nocturnal hemoglobinuria clone its occurrence and persistence (median - 0.34% (0.1%-6.2%)) was noticed. According to the results of study, alteration of sizes of paroxysmal nocturnal hemoglobinuria clone or its occurrence develop in case of response to ISP and, most probably, depend on advantage of growth in the process of repair of normal (GPI positive) or clonal (GPI negative) hemopoiesis. To acquire more reliable conclusions will be possible through development of techniques of molecular diagnostic simultaneously with dynamic observation of course of disease in the given patients.

Sonochemical approaches to enhanced oil recovery

Oil production from wells reduces with time and the well becomes uneconomic unless enhanced oil recovery (EOR) methods are applied. There are a number of methods currently available and each has specific advantages and disadvantages depending on conditions. Currently there is a big demand for new or improved technologies in this field, the hope is that these might also be applicable to wells which have already been the subject of EOR. The sonochemical method of EOR is one of the most promising methods and is important in that it can also be applied for the treatment of horizontal wells. The present article reports the theoretical background of the developed sonochemical technology for EOR in horizontal wells; describes the requirements to the equipment needed to embody the technology. The results of the first field tests of the technology are reported.

An ultrasonic technology for production of antibacterial nanomaterials and their coating on textiles

A method for the production of antibacterial ZnO nanoparticles has been developed. The technique combines passing an electric current with simultaneous application of ultrasonic waves. By using high-power ultrasound a cavitation zone is created between two zinc electrodes. This leads to the possibility to create a spatial electrical discharge in water. Creation of such discharge leads to the depletion of the electrodes and the formation of ZnO nanoparticles, which demonstrate antibacterial properties. At the end of this reaction the suspension of ZnO nanoparticles is transported to a specially developed ultrasonic reactor, in which the nanoparticles are deposited on the textile. The nanoparticles are embedded into the fibres by the cavitation jets, which are formed by asymmetrically collapsing bubbles in the presence of a solid surface and are directed towards the surface of textile at very high velocities. Fabrics coated with ZnO nanoparticles by using the developed method showed good antibacterial activity against E. coli.

Ultrasonically improved galvanochemical technology for the remediation of industrial wastewater

Two general methodologies adopted for the decontamination of industrial wastewater containing oil and metal ions are flocculation and coagulation. Both methods require the addition of chemicals and in the case of electrocoagulation the additional use of electrical power. Another methodology that was developed in Russia some years ago involves the production of Fe2O3 particles as coagulants by a galvanochemical reaction between iron and coke. Both of these materials are inexpensive and generally available in bulk. Ultrasonic processing of the particles generated in this reaction reduces the particle size of the Fe2O3 particles and provides surface cleaning making them more effective. Trials have proved their efficiency for the decontamination of wastewater made up in a laboratory and real wastewater from a carriage cleaning station on the St. Petersburg Metro. A mathematical model for the process has been developed.

Ultrasonic technology for enhanced oil recovery from failing oil wells and the equipment for its implemention

A new method for the ultrasonic enhancement of oil recovery from failing wells is described. The technology involves lowering a source of power ultrasound to the bottom of the well either for a short treatment before removal or as a permanent placement for intermittent use. In wells where the permeability is above 20 mD and the porosity is greater than 15% ultrasonic treatment can increase oil production by up to 50% and in some cases even more. For wells of lower permeability and porosity ultrasonic treatment alone is less successful but high production rates can be achieved when ultrasound is applied in conjunction with chemicals. An average productivity increase of nearly 3 fold can be achieved for this type of production well using the combined ultrasound with chemical treatment technology.