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Abstract

Non-alcoholic fatty liver disease is one of the most common chronic liver diseases with unclarified pathomechanism and without evidence-proven therapy. Dietary polyphenols, targeting oxidative stress, are at the center of investigations. Our aim was to examine the effects of a polyphenol rich extract on metal element homeostasis and transmethylation ability in non-alcoholic fatty liver model. A ten-day rat model was used (control group, hyperlipidemic group with fat-rich diet, hyperlipidemic group with fat-rich diet and polyphenol supplementation, N = 8 in each group). The hyperlipidemic diet increased the concentration of the majority of the elements with significantly higher contents of B, Co, Cu, Fe, Mg, Mn, Na, Ni, P, Se, Si, and Zn in the liver. Further elevation of Al, Pb, and Sn concentrations could be observed in polyphenol supplemented animals. The polyphenol supplement unexpectedly decreased the transmethylation ability of the liver (132.00 vs. 114.15 vs. 92.25 HCHO μg g−1) further. The results emphasize the possible role of altered metal and non-metal element concentrations and decreased transmethylation ability in the pathomechanism of fatty liver disease. Dietary supplementation with natural compounds may have undesirable effect as well, there is the necessity to improve the efficacy of polyphenol formulations because of their low oral bioavailability.

Open access
Acta Alimentaria
Authors:
K.O. Bartha
,
L. Csengeri
,
A. Lichthammer
,
A. Erdélyi
,
J. Kubányi
, and
Zs. Szűcs

Abstract

COVID-19 lockdown affects people's daily routine and has an impact on their lifestyle. Recent studies documented associations between body weight changes and children's lifestyle during social isolation. Childhood obesity is associated with a higher risk of COVID-19 severity and mortality. Our aim was to assess the effects of lockdown due to the COVID-19 pandemic on children's sleep, screen time, physical activity, and eating habits. 387 parents of five elementary school students between 16 and 26 June 2020 were interviewed through an online questionnaire. Physical activity level decreased (63.8%), sleep (60.9%) and screen (5.64 ± 3.05 h/day) times and food intake (39.8%) increased. 80.6% of parents reported changes in children's diet: increased consumption of fruits and vegetables (32.4%), breakfast (15.5%), water and sugar-free beverages (17.6%), snacks (40.4%), sugary drinks (9.9%) was observed. Body weight increased in 44.4% of children. The results of the survey conducted under GYERE®-Children's Health Program are in line with the international literature findings: body weight change during the quarantine is significantly associated with food intake, snacking, sugary drinks, and we also found association with fruit and vegetable consumption and lack of breakfast. Effective strategies and electronic health interventions are needed to prevent sedentary lifestyle and obesity during lockdown.

Open access

Abstract

Cassava is used as a staple food in many developing countries despite its low nutrient density. Fortification of cassava diets is needed for the prevention of malnutrition and achievement of food security. Cassava-soybean complementary foods were formulated from natural and solid state fermented cassava complemented with soybean. The proximate composition, physicochemical properties, nutritional quality, and sensory properties of the samples were determined (Table 2). The moisture content (7.51%) and ash (3.81%) content of the solid state fermented (SSF) cassava flour complemented with un-defatted soybean flour was significantly higher (P < 0.05) than of the other samples. Solid state fermentation (SSF) led to the highest reduction in viscosity (from 2,855 to 2,052 cPs). Average weight gain and protein efficiency ratio (PER) of experimental animals fed SSF cassava were the highest. The colour and aroma of SSF diets and that of fermented cassava samples were similar (P > 0.05). The texture of diets from SSF cassava were inferior (P < 0.05) to the other samples. Solid state fermentation of cassava with Rhizopus oligosporus and supplementation with soybean can be used to produce a complementary food that is nutrient dense and nutritionally adequate, although the texture of the product might need to be improved.

Restricted access
Pollack Periodica
Authors:
Orest Voznyak
,
Nadiia Spodyniuk
,
Olena Savchenko
,
Iryna Sukholova
,
Mariana Kasynets
, and
Oleksandr Dovbush

Abstract

The work is devoted to study of thermal efficiency of heating convectors with aluminum ribbing to ensure comfortable indoor conditions. The purpose of this paper is to evaluate theoretically and experimentally the thermal efficiency of convector-type heaters with aluminum ribbing, to implement numerical simulation and to obtain dependencies for determination of thermal characteristics of convector-type heaters with aluminum ribbing, ensuring of a proper both indoor climate in the premise and energy saving. A nomogram of interdependence between heat amount, heat carrying medium flow rate, the initial and final temperatures was created. Heat quantity increases with increasing heat carrying medium flow rate, the inlet temperature and decreases with increasing of the exit temperature.

Restricted access
Pollack Periodica
Authors:
Orest Voznyak
,
Nadiia Spodyniuk
,
Olena Savchenko
,
Iryna Sukholova
,
Mariana Kasynets
, and
Oleksandr Dovbush

Abstract

The work is devoted to study of thermal efficiency of heating convectors with aluminum ribbing to ensure comfortable indoor conditions. The purpose of this paper is to evaluate theoretically and experimentally the thermal efficiency of convector-type heaters with aluminum ribbing, to implement numerical simulation and to obtain dependencies for determination of thermal characteristics of convector-type heaters with aluminum ribbing, ensuring of a proper both indoor climate in the premise and energy saving. A nomogram of interdependence between heat amount, heat carrying medium flow rate, the initial and final temperatures was created. Heat quantity increases with increasing heat carrying medium flow rate, the inlet temperature and decreases with increasing of the exit temperature.

Restricted access

Abstract

With the gradual improvement of urban construction, more and more experts and the public realized that the speed of urban development be reasonable, which caused urban regeneration to turn to a new-minded “urban micro-regeneration”. “Micro-regeneration” is an extension of the concept to the direction of urban construction. The concept of micro-regeneration was first applied to the regeneration of individual buildings in the old city. The research on the intervention of public art in urban micro-regeneration is still in its infancy in China. Based on practice, this paper explores the possibility of public art's intervention in urban micro-regeneration.

Open access

Abstract

With the gradual improvement of urban construction, more and more experts and the public realized that the speed of urban development be reasonable, which caused urban regeneration to turn to a new-minded “urban micro-regeneration”. “Micro-regeneration” is an extension of the concept to the direction of urban construction. The concept of micro-regeneration was first applied to the regeneration of individual buildings in the old city. The research on the intervention of public art in urban micro-regeneration is still in its infancy in China. Based on practice, this paper explores the possibility of public art's intervention in urban micro-regeneration.

Open access
Progress in Agricultural Engineering Sciences
Authors:
N. Anter
,
M. Y. Guida
,
M. Kasbaji
,
A. Chennani
,
A. Medaghri-Alaoui
,
E. M. Rakib
, and
A. Hannioui

Abstract

In this scientific paper, thermochemical conversion of redwood (RW) was studied. Using the thermogravimetric analysis' technique (TGA), the thermal behavior of RW samples was examined at four heating rates ranging from 5 to 20 K min−1 in inert atmosphere between 300 and 900 K. Two main objectives have been set for this study; the first one was the determination of the kinetic decomposition parameters of RW (Pinus sylvestris L.), and the second one was the study of the variation of characteristic parameters from the TG-DTG curves of the main RW's components, such as; cellulose, hemicellulose and lignin. The kinetic analysis was performed using three isoconversional methods (Vyazovkin (VYA), Friedman (FR) and Flynn-Wall-Ozawa (FWO)), Avrami theory method and the Integral master-plots (Z(x)/Z(0.5)) method to estimate activation energy (E a ), reaction order (n), pre-exponential factor (A) and model kinetic (f(x)) for the thermal decomposition of cellulose, hemicellulose and lignin components.

The DTG and TG curves showed that three stages identify the thermal decomposition of RW, the first stage corresponds to the decomposition of hemicellulose and the second stage corresponds to the cellulose, while the third stage corresponds to the lignin's decomposition. For the range of conversion degree (x) investigated (0.1 ≤ x ≤ 0.7), the mean values of apparent activation energies for RW biomass were 127.60–130.65 KJ mol−1, 173.74–176.48 KJ mol−1 and 197.21–200.36 KJ mol−1 for hemicellulose, cellulose and lignin, respectively. Through varied temperatures from 550 to 600 K for hemicellulose, from 600 to 650 K for cellulose and from 750 to 800 K for lignin, the corresponding mean values of reaction order (n) were 0.200 for hemicellulose, 0.209 for cellulose and 0.047 for lignin. The pre-exponential factor's average values for three components of RW ranges from 0.08 × 1012 s−1 to 2.5 × 1012 s−1 (A hemicellulose = 1.09 × 1012 s−1), 0.10 × 1014 s−1 to 0.28 × 1014 s−1 (A cellulose = 0.17 × 1014 s−1) and 3.07 × 1016 s−1 to 3.69 × 1016 s−1 (A lignin = 3.33 × 1016 s−1), respectively. The experimental data of RW had overlapped the D 4, D 2 and F 3 in the conversion degree of 10–30%, 30–55% and 55–70% for the three components, respectively.

Restricted access
Pollack Periodica
Authors:
Réka Wittmanová
,
Jaroslav Hrudka
,
Ivana Marko
,
Andrea Raczková
, and
Štefan Stanko

Abstract

Dynamical modeling in water supply and treatment and wastewater treatment helps to understand the flow in the networks. Therefore, it is important to incorporate dynamic modeling into the design and assessment processes and operation for the future of urban drainage systems.

The aim of this paper was using a mathematical model to analyze the functionality of combined sewer networks during a precipitation event on 13 October 2020. The analysis was performed based on the results from the assessment of the hydraulic capacity of the sewer network using the MOUSE model in the MIKE URBAN software. This study results that the evaluated sewer network does not fulfill his purpose during heavy rainfall events.

Restricted access
Pollack Periodica
Authors:
Réka Wittmanová
,
Jaroslav Hrudka
,
Ivana Marko
,
Andrea Raczková
, and
Štefan Stanko

Abstract

Dynamical modeling in water supply and treatment and wastewater treatment helps to understand the flow in the networks. Therefore, it is important to incorporate dynamic modeling into the design and assessment processes and operation for the future of urban drainage systems.

The aim of this paper was using a mathematical model to analyze the functionality of combined sewer networks during a precipitation event on 13 October 2020. The analysis was performed based on the results from the assessment of the hydraulic capacity of the sewer network using the MOUSE model in the MIKE URBAN software. This study results that the evaluated sewer network does not fulfill his purpose during heavy rainfall events.

Restricted access