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Modified cellulose materials are finding increasing application in electronics, because of the need for more environmental-friendly electronic circuits. The papers prepared from poly(ethyleneimine)-TiO2-anthocyanin-modified cellulose fibres are completely environmentally friendly and can be applied to the construction of photocells or photo-/humidity sensors. To better understand the mechanisms of electrical conductivity of the said cellulose composites, the effect of humidity (RH = 9% → 100%) on its dielectric properties is presented in this article. The possibility of trapping the negative and positive charges in the composite under different humidity conditions is also examined. A large number of studies suggest that proton conductivity, stimulated by humidity, is the dominant mechanism of electrical conductivity in cellulose-based materials. The results presented in this paper indicate that the electronic conductivity mechanisms also play a significant role in papers prepared from poly(ethyleneimine)-TiO2-anthocyanin-modified cellulose fibres. [ABSTRACT FROM AUTHOR]

There is a resurgence of regional and local products in Hungary today. Thanks to the development of local businesses, communities and towns are also able to derive a number of economic, environmental, social and cultural advantage. The products in focus are emerging in tourism more often, frequently acting as foundations of tourist attractions built upon them, providing the receiving end with a unique and authentic force of attraction that follow the present trends. The aim of our study was to explore tourists’ needs for local products and the role of local food in regional tourism services. The region of our empirical research was the area of Baranya and Tolna counties in Southern Hungary where we analyzed local producers’ and their consumers’ attitudes towards local products.

Studies have proven the effectiveness of different weight-bearing exercise interventions for diabetic patients with neuropathy; however, several adverse effects were reported using solid surfaces. Thus, in the present study, we investigated the effects of a novel sand exercise training intervention on biomechanical and functional parameters in seven diabetic patients (age = 62.7 ± 9.7 years) with neuropathy. Patients underwent a 12-week sand exercise training program, using strengthening, stretching, balance, and gait exercises. They were tested for ankle plantar- and dorsiflexion peak torque, active range of motion (ROM), timed up and go (TUG), and bilateral static balance. EMG activity of tibialis anterior (TA), gastrocnemius medialis (GM), and lateralis (GL) muscles were measured during unilateral isometric contraction in plantar- and dorsiflexion. In the intervention period, plantarflexion peak torque improved significantly ( p = 0.033), while dorsiflexion torque remained unchanged. Plantar- and dorsiflexion ROM increased ( p = 0.032) and ( p = 0.021), respectively. EMG activity of GM ( p = 0.005) and GL ( p = 0.002) measured during dorsiflexion and postural sway in the balance test, as well as time to complete the TUG test, decreased significantly ( p = 0.021) and ( p = 0.002), respectively. No adverse effect was reported during the intervention period. We concluded that sand exercise training can be a safe and effective method to improve plantarflexion strength, ankle flexibility, and balance, which is reflected in better gait function in patients with diabetic peripheral neuropathy (DPN).

The current work investigates the shear stress distribution in hydrodynamic cavitation reactors with two different geometries using CFD simulations. Venturi type (positive geometry) and bore (negative geometry) were used to induce cavitation. Experimental validation of the predictions from simulations was also conducted by calculating the reduction rate in the colony count of Legionella pneumophila, a pathogenic bacterial strain. Both the numerical and experimental studies revealed the significant influence of the shape of the cavitation-inducing geometry on the flow characteristics and the distribution of shear stress. The simulation data indicated high shear stress formation in the positive geometry as a venturi, with the cavitation ranges for the two reactors being far apart from each other. The experimental study also confirmed that the flow conditions in the venturi-type reactor were more favourable compared to the bore geometry, resulting in a bacterial reduction efficiency as high as 99.98%. It was clearly demonstrated that the geometry of the cavitating device plays a crucial role in deciding the shear stress and its efficacy for the desired applications as per the predictions of the simulation model validated by the experimental results., (© 2022. The Author(s).)

Photoabsorption properties of cellulose fibres under continuous and modulated irradiation were investigated in situ by the use of reversed double-beam photoacoustic spectroscopy (RDB-PAS). This photoacoustic (PA) measurement enabled observation of ultraviolet- and visible light-induced, electron trap filling, and reductive change on the surface of the fibres. Energy-resolved measurements and analysis of the kinetics of photoinduced de-excitation suggested that electrons that accumulated in the different cellulose crystalline phases had moderate reactivity toward molecular oxygen. Saturation limits of the intensities of the PA and RDB-PAS signals under de-aerated conditions in the presence of surface-adsorbed methanol were estimated for softwood and hardwood cellulose samples. The results suggest that the RDB-PAS technique is a feasible method for the estimation of the electron trap distribution, which is a potential measure of the density of crystalline cellulose defects., (© 2022. The Author(s).)

Hydrodynamic cavitation treatment was used for the functional inactivation of quorum-sensing lactone molecules of Pseudomonas aeruginosa. Hydroxyl radicals formed as well as the shear effects during the cavitation process induced the inactivation of the signal molecules through hydrolysis reaction coupled with bacterial destruction. Concentration of two different types of homoserine lactones (HSL) molecules was tested after the treatment at various rotational speeds. It was found that the strongest effects can be achieved at speeds > 2000 rpm. This value is considered as an onset speed of dominant cavitation, and it is in agreement with literature data. The experimental trends were in agreement with the calculations based on the finite element modelling, which show a significant increase in average shear stress at higher rotational speeds. Overall, the work has demonstrated the possible effects of hydrodynamic cavitation on the quorum-sensing molecules of Pseudomonas aeruginosa for the first time.

Background: The proportion of elderly is on the rise both in Europe and in Hungary. The challenge is to increase the number of years spent in good health as well as to improve quality of life of those 60 years and above. This study focuses on the impact of physical activity on this age group., Methods: A nationally representative sample of 2000 respondents were surveyed in an age range of 15-74. Our data concerns those being 60-74 years of age. The focus of our investigation was level and impact of physical activity in the group above. First, we used Chi-squared tests and correspondence analysis to identify the deviation in the answers of different groups in our sample. After we built a hierarchical linear regression model to get a deeper understanding of the impact of physical activity for elderly., Results: Those reporting no physical/sports activity at all have to do with the negative culture of exercising. Only 9.3% reported being engaged with any sports; 72% reported no regular exercising throughout their lives. The relationship between sport activity and self-reported health was significant (p = 0.009, Cramer's V = 0.2). Elderly were characterized by walking, hiking and less intense sports., Conclusions: Those who actively exercised in this research reported better health outcomes than those who stopped or had never been engaged in any sports. We conclude that of all variables tested, physical activity was most effective to improve personal health of the elderly in this sample. Compared to European data on physical activity of elderly populations, Hungary seems to fall behind and needs to consider concentrated efforts to improve the future health of its senior populace.

One way of satisfying increased market demand and simultaneously achieving a reduced environmental load in the industrial paper production is the use of fibrous agricultural residues. The aims of this study were i) to investigate the effect of alkaline - hydrodynamic cavitation (HC) pre-treatments on the delignification of Miscanthus × giganteus stalks (MGS) and ii) establishing the suitability of MGS as feedstock and their exploitation in pulp and paper manufacturing. It was demonstrated that the proposed treatment is an efficient delignification method for the non-wood fiber sources, such as miscanthus. A significant outcome of this work was the observation that HC treatment preserved the fibres lengths and surface quality of raw MGS, but at the same time increased the amount of kinked and curled fibers present in cavitated miscanthus fibers. The average miscanthus fiber length was found to be relatively short at 0.45 (±0.28) mm, while the slenderness ratio, the flexibility coefficient and Runkel ratio values were calculated to be 28.13, 38.16 and 1.62, respectively. The estimated physical properties of MGS pulp hand-sheets were 24.88 (±3.09) N m g -1 as the tensile index, 0.92 (±0.06) kPa m 2 g -1 as the burst index and 4.0 (±0.37) mN m 2 g -1 as the tear index. Overall the current work demonstrated effective use of hydrodynamic cavitation for improving the processing in pulp and paper manufacturing., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

Ultrasonication was used to extract bioactive compounds from Cannabis sativa L. such as polyphenols, flavonoids, and cannabinoids. The influence of 3 independent factors (time, input power, and methanol concentration) was evaluated on the extraction of total phenols (TPC), flavonoids (TF), ferric reducing ability of plasma (FRAP) and the overall yield. A face-centered central composite design was used for statistical modelling of the response data, followed by regression and analysis of variance in order to determine the significance of the model and factors. Both the solvent composition and the time significantly affected the extraction while the sonication power had no significant impact on the responses. The response predictions obtained at optimum extraction conditions of 15 min time, 130 W power, and 80% methanol were 314.822 mg GAE/g DW of TPC, 28.173 mg QE/g DW of TF, 18.79 mM AAE/g DW of FRAP, and 10.86% of yield. A good correlation was observed between the predicted and experimental values of the responses, which validated the mathematical model. On comparing the ultrasonic process with the control extraction, noticeably higher values were obtained for each of the responses. Additionally, ultrasound considerably improved the extraction of cannabinoids present in Cannabis., Practical Application: Low frequency ultrasound was employed to extract bioactive compounds from the inflorescence part of Cannabis. The responses evaluated were-total phenols, flavonoids, ferric reducing assay and yield. The solvent composition and time significantly influenced the extraction process. Appreciably higher extraction of cannabinoids was achieved on sonication against control., (© 2018 Institute of Food Technologists®.)

Agricultural and forest residues obtained after harvesting are promising renewable sources, suitable as a source of pulp for cellulose nanocrystal manufacturing. Cavitation-assisted softening of the lignin-carbohydrate matrix offers sample opportunity for cellulose fibril liberation and degradation of amorphous cellulose. The present work addresses cavitation assisted cellulose fibril and crystal liberation and film forming properties of the supernatant phase of treated agricultural and forest residues. The effectiveness of this method has been evaluated according to crystallinity indices and hydrogen bond energies, as measured by FT-IR analysis. It has been observed that the use of cavitation increased the crystallinity and caused partial removal and degradation of the lignin matrix. Overall, it appears that considerable improvement of crystallinity can be obtained from agricultural and forest residues through the use of cavitation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Cellulose fiber sheets impregnated with saccharide capped-ZnO nanoparticles were used as bioactive materials for antibody immobilization. First, ZnO nanoparticles were synthesized in the presence of glucose (monosaccharide), sucrose (disaccharide) as well as alginic acid and starch (polysaccharides). The pine cellulose fibers were then modified by the obtained saccharide capped nanoparticles and further incorporated into the sheets. The presence of ZnO significantly improved the immobilization of the antibodies on the surface of the sheets. After rewetting the alginic acid-ZnO modified sheets with saline solution, the retention of antibodies was about 95%. A high degree of the immobilization of biomolecules is an important feature for possible fabrications of bioactive- or biosensing-papers and we successfully tested the sheets on the detection of blood types using (A, B, and D blood antibodies). The ZnO nanoparticles affected also the other properties of the sheets. The ZnO-modified fiber sheets showed higher values of tensile index (strength), smoothness and opacity, while the value of porosity was substantially lower than that of the unmodified sheet. The presence of ZnO nanoparticles provided also the antimicrobial activity to the sheets. They showed a strong activity against bacteria (Escherichia coli and Staphylococcus aureus) and strong resistance to the attack of cellulase producing fungus Gloeophyllum trabeum., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A silver nanoparticle colloid was prepared by a modified Tollens method using d-glucose as the reduction agent. The obtained nanoparticles were used for the modification of pine, linter and recycled cellulose fibers. Although the silver contents were relatively low (0.05-0.13 wt.%), the cellulose-sheets prepared from the modified fibers show improved mechanical and viscoelastic properties. The tensile index (strength) increased with up to 30% in comparison to the index of the sheets obtained from the untreated fibers. The influence of the nanoparticles on the viscoelastic properties of the cellulose sheets was investigated by dynamic mechanical analysis (DMA) in the temperature range from -120 to 20 °C and with a force frequency of 100 Hz. A broad relaxation transition positioned at -80 °C was observed in the loss modulus spectrum of all the cellulose sheets, while the Ag-modified sheets exhibited higher storage moduli values in the whole temperature range. The antimicrobial activity tests show that the pine, silver and recycled cellulose fiber sheets with silver nanoparticles can be successfully employed to prevent the viability and growth of the common pathogens Staphylococcus aureus, Escherichia coli and Candida albicans., (Copyright © 2012 Elsevier Ltd. All rights reserved.)