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Authors: A.I. Korkmaz, H. Akgul, M. Sevindik and Z. Selamoglu

Lichens are symbiotic associations that are formed by fungi and algae or cyanobacteria. The number of lichen species investigated pharmaceutically is still very low at present. The present study aims to determine the antioxidant activities, antibacterial activities, DNA protective activities, and oxidative stress status of Bryoria fuscescens (Gyeln.) Brodo & D. Hawksw., Parmelina tiliacea (Hoffm.) Hale, and Umbilicaria decussata (Vill.) Zahlbr. Lichens were extracted with ethanol in the Soxhlet device. The DPPH method was used to determine antioxidant activities. DNA protective activity was determined using pBR322 supercoil DNA. Antibacterial activity was determined with dilution test on 5 different species of bacteria (Enterocossus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus). Total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were defined with Rel Assay Diagnostics kits. It was observed that DPPH free radical scavenging activities in lichen ethanol extracts increased with increasing concentration. The highest antioxidant activity was observed in B. fuscescens and the lowest activity was determined in U. decussata. It was also determined that the ethanol extracts of all lichen samples had DNA-protective activity. The highest antibacterial activity was detected in B. fuscescens, while the lowest activity was detected in U. decussata. It was determined that B. fuscescens had the highest oxidative stress index and U. decussata had the lowest value. It appears that the ethanol extracts of the lichen samples utilized in the study could be used as an alternative and complementary resource in medical treatment.

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Authors: É. Varga-Visi, B. Toxanbayeva, G. Andrássyné Baka and R. Romvári

The fat content of Bologna-type turkey sausages was partially replaced with pea fiber or potato starch. Textural properties of full fat turkey sausage were mainly restored in sausages when fat was partially replaced with some levels of pea fiber (0.6, 1.2%) or potato starch (1.9%). Authors observed significant correlation (P<0.01) between instrumentally measured values of hardness and chewiness and sensory ratings of low fat sausages.

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The effect of sprouting of onions on total phenolic content, antioxidant activity, and anthocyanin profile of freeze dried powders produced from Indian onion cultivars was examined. Sprouting was carried out at an average light intensity of 64 Lumen, average relative humidity of 80.2%, and average temperature of 15.22 °C for three weeks. Two way analyses of data revealed significant (P<0.05) effect of sprouting and cultivar on functional composition of freeze dried powders. In all sprouted powder samples, there were significant (P<0.05) enhancements in total phenolic content, total flavonoid content, vitamin C content, antioxidant activity, and colour due to increase in anthocyanin contents. The anthocyanin profile depicted an increase in total anthocyanin concentration in powders developed from all four cultivars with the highest increase in powder from PRO-6 (23.87–27.15 mg kg−1), followed by Punjab Naroya (9.97–12.92 mg kg−1), commercial (7.15–8.43 mg kg−1), and Punjab White cultivar (3.45–4.09 mg kg−1).

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A GC-FID method for major volatile analysis in cider and wine was validated under the requirements of the ISO/IEC 17025 regulation using a split mode injection. This method presented a good linearity (R2>0.999, Cm>99%), a wide range of calibration, the maximum random errors for repeatability and intermediate precision were 5% and 8%, respectively, and the maximum limit of quantification and limit of detection were 14.1 mg l–1 and 4.6 mg l–1, respectively. Trueness, expressed as recovery (%), was successfully validated by means of two different methods, standard addition (92–110%) and comparison against reference materials (93–115%). Expanded uncertainty estimated at 95% confidence level ranged between 11% for methanol and 7% for allyl alcohol. The validated method was successfully applied for the analysis of major volatiles in ciders and wines, and to detect yeast and lactic acid bacteria spoilage.

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The design methods of the load bearing glass columns developed extremely in the last years. Numerous glass researchers have been trying to optimize the glass structures in terms of cost-effectiveness and safety. The authors carried out several laboratory experiments to analyze the key factors of the glass column design. Factors are investigated in the present article for example the influence of the fixing at the end of the glass columns, which essentially modifies the load bearing capacity of structures. The efficiency of the gluing of the interlayer foil (the coupling parameter) was analyzed based on the individual laboratory experiments.

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A major problem related to heat treatment of milk is formation of deposits. This is due to the chemical alteration of β-lactoglobulin protein that leads to formation of coatings on the walls of the equipment. These deposits induce losses in the thermal performance of the heat exchanger. In order to provide an adequate prediction of these deposits, we present a two-dimensional (2D) modelling study of the channel of a plate heat exchanger. Compared with the former studies, where the domain is related to a single plate, our work is related to the area between the two plates. This approach will allow a better understanding and description of the evolution and behaviour of β-lactoglobulin protein. Equations for fluid flow, energy, and fouling were resolved. Special boundary conditions had been implemented to link the amount of deposits with thermal transfer. Predicted results for the amount of fouling deposit on the wall were validated by comparisons with experimental data available in literature. The behaviour of β-lactoglobulin protein was studied by analyzing its distribution in the channel.

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Authors: A. Nath, S. Mondal, A. Csighy, M.A. Molnár, K. Pásztorné-Huszár, Z. Kovács, A. Koris and Gy. Vatai

In the dairy industry different types of prebiotics, such galacto-oligosaccharide, lactulose, lactosucrose, tagatose, lactitol, lactobiono- and glucono-δ-lactone are synthesized through different chemical and biochemical reactions (hydrolysis, transgalactosylation, isomerization, fructosyl-transfer, reduction, and oxidation) as well as microbial fermentation processes using raw whey or isolated lactose as feedstock. Lactose-derived prebiotics have several functional and nutritional values. The biochemical activities of lactose-based prebiotics are expressed in the presence of probiotics (lactic acid bacteria, yeasts, Bacillus spp.). Galacto-oligosaccharide and lactosucrose reduce the risk of bowel disorder (diarrhea), inflammatory bowel disease (ulcerative colitis and crohn’s disease), and colon cancer. Galacto-oligosaccharide helps colonic absorption of minerals (iron, magnesium and calcium) and prevents osteoporosis. Lactulose, galacto-oligosaccharide, and lactitol promote laxative activity. Furthermore, lactulose may decrease the risk of hepatic encephalopathy. Prebiotics have low calorific value and glycemic index. Galacto-oligosaccharide and tagatose reduce the risks of hyperglycemia (Type 2 diabetes) and low density lipid (lipoprotein) accumulation in blood stream. Moreover, prebiotics improve immunomodulation, which reduces the risk of respiratory infection and allergies. This review describes unique biochemical mechanisms of several types of lactose-derived prebiotics.

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The paper unveils a black box model-based self healing strategy to suppress the ill effects of stuck-at-faults occurring in combinational circuits. The primary theory endeavours to attach a sense of reliability in the performance of digital systems and makes them insensitive to the negative impact of faults present in the system. The proposed methodology employs a dynamic fault tolerant approach to protect digital systems from the incursion of stuck-at-faults and enables the system to come up with fault free outputs. The simulation results affirm the authenticity of the proposed strategy to cancel out the influence of faults and facilitate the system to heal itself. The work utilizes the attributes of an FPGA to demonstrate the practical viability of the proposed approach. The performance analysis endorses the definite dominance of the proposed healing scheme over the traditional Triple Modular Redundancy [TMR] in terms of fault coverage and area overhead.

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Authors: R. Tömösközi-Farkas and E. Horváth-Szanics
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Authors: L.E. Morales, G. Griffith, V. Wright, E. Fleming, W. Umberger and N. Hoang

Retail beef markets not offering objective grade indicators in-store leave consumers uncertain about the quality of beef they purchase. The introduction of fresh brands can better meet consumers’ expectations. Willingness-to-pay for ‘ideal’ quality cuts represents the maximum premiums brands could achieve. Using Australian consumers’ survey data, the maximum premiums are modelled using zero-inflated negative binomial models. Results indicate that buyer’s characteristics and perceptions about product attributes influence the premiums for high-quality beef that consumers are willing to pay for a cut considered ‘ideal’, indicating the maximum premium that brands could achieve in relevant segments. The premiums indicate there is substantial potential for beef cuts that reduce purchase risk by more assuredly meeting buyer’s preferences in Australia.

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The spoilage of meat products (N>5×106 CFU g−1) can be delayed by cooling and low-temperature storage and transport. The highest extent of interruption in the cold chain occurs at the time of delivering the meat product to the individual’s home after purchasing it. Consumer behaviour and the ambient temperature largely influence the shelf life of products. In our research, we examined the buying habits of customers in Hungary. Based on these results, we carried out the cold chain interruption of vacuum-packed sliced ham (1, 2, 3 h) under laboratory conditions, at temperatures of 15, 25, and 35 °C. The microbial count was determined by a quick method based on redox-potential measurement in two-three days until the products were deteriorated. Our experiments resulted in the expected outcomes; however, we concluded that even average customer habits (1 h cold chain interruption) at higher temperature periods (T>20 °C) decrease the shelf life of ham by 6 days. We set up a mathematical model through which the changes of microbial counts can be determined as a function of product temperature changes, the period of delivery, and the subsequent period of cold storage. R2=0.9 correlation was given between predicted and measured microbial counts (logN).

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Fruits and vegetables can be transmission vehicles of human opportunistic and obligate pathogenic bacteria, persisting in inner tissues for shorter or longer periods or colonizing the plants as facultative endophytes. In this study we investigated the ability of commensal E. coli and pathogenic L. monocytogenes strains to internalize sweet pepper seedlings via seed bacterization, as germinating seeds and roots are important infiltration sites for entry of enteric bacteria. By combining cultivation dependent and independent (PCR and FISH-CLSM) techniques we could not detect stably or transiently colonized inoculated bacteria in 6–7 weeks old pepper seedlings, suggesting that there is low risk associated with internalized enteric or human pathogenic bacteria via germinating seeds in sweet pepper.

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The aim of this article is the comparison of input options of river boundary condition of MODFLOW - three-dimensional numerical simulation model of groundwater flow. The water level in stream flowing through territory of hydrogeological layer can be computed via three built-in modules: River, Stream and Streamflow-Routing. In this study the code MODFLOW is used to simulate idealized aquifer and stream. The differences between computed groundwater table showed to be minimal, thus in case of modules Stream and Streamflow- Routing they are equally usable as using module River with external one or two-dimensional simulation of surface water flow, which is more time-consuming process. However, this applies only to idealized, simplified conditions of the modeled environment. For more complex simulation of flow in streams with irregular structure of the streambed is necessary to use either an external simulation or use the Streamflow-Routing module, which includes the possibility to enter more complex hydraulic flow parameters in the model.

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Smart pointers play an important role in bypassing memory leaks in C++. Since C++11 standard the smart pointers have become widely-used tools because they let the programmers not to deal with memory deallocation. However, abstraction penalty occurs because of this convenience. Overhead is related to runtime, memory usage and compilation time. There are many different smart pointers in the standard library. However, the performance difference between the smart pointers and raw pointers is not measured before. This paper presents an analysis of their effectiveness. An alternative approach to the C++17’s optional construct is searched for.

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The aim was the perfection of an analytic examination, which describes the track deterioration process, characterized the correspondences more precisely and better to use in practice. This method was based on the destruction’s theory of the railway track geometry and it exploited the possibilities of recent computer technology. More than one million measuring car (FMK-004) data were processed than analyzed and defined by configuring and programming a new method. The results of this method were descriptive functions, which afford interpretable information about the geometrically destruction’s occurrences of the different railway lines.

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e-Procurement adoption by architects in the Nigerian building industry was investigated using data derived via a questionnaire survey of 75 architects in consulting and contracting firms, government and clients’ organizations. The data were analyzed using descriptive statistics, Pearson product-moment correlation and content analyses, and the results reveal that most of the organizations employing architects were not using e-Procurement. However, the very few adopters identified used e-mails and websites in communicating, exchanging project information, and sourcing for building services, materials and equipment. The key barriers to the uptake of e-Procurement among architects in the survey were unreliable power supply, low level of awareness among people; and the lack of forum to exchange ideas on e- Procurement use. The paper emphasized the need to address these challenges to ensure a critical mass uptake of e-Procurement by architects in Nigeria.

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Self-compacting concrete has gained a wide range of applications as a result of its unique properties, which can offer high strength and durable type of concrete with the proper selection of the raw materials. The purpose of this study was to show the effect of the use of high dosage of air entraining admixture on the properties of self-compacting concrete. An experimental investigation on the frost-salt scaling resistance of conventional and air entraining selfcompacting concrete incorporating slag-blended cement and supplementary cementitious materials was carried out. Further fresh and hardened properties tests including slump flow, V-funnel, compressive strength, splitting tensile strength, air void characteristics and water absorption tests were performed to obtain an objective evaluation between air and non-air entrained self-compacting concrete mixtures. Air void characteristics were evaluated through the automated image analysis procedure to enrich this investigation. Results indicate the following: the air entraining admixture highly decreased the compressive strength up to 52% and the metakaolin was the governing supplementary cementitious material concerning the scaling resistance and water absorption in comparison with the silica fume.

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Passion fruit juice (PFJ) has a delicate flavour, very susceptible to thermal degradation. This study pursued to test the effect of sonication as non-thermal preservation method on some quality parameters of PFJ. The effect of ultrasound (20 kHz, 263 W, 89.25 μm) on the indigenous microflora, colour, pH, and ascorbic acid content of PFJ was studied. Firstly, the kinetic of microbial inactivation was determined for aerobic mesophilic bacteria and yeasts. Data was fitted to Weibull model, and a treatment time of 8 min was selected for stability studies. To this, untreated and sonicated juice was stored at 4 and 10 ºC up to 10 days and microbial quality, instrumental colour, pH, and ascorbic acid content were evaluated. In general, ultrasound kept juice microbiologically stable for up to 10 days at 4 ºC without markedly affecting other parameters evaluated. Ultrasound seems suitable to stabilize PFJ microbiologically.

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The objective of this study was to assess the influence of three different starter culture combinations and two scalding temperatures on the organic and fatty acid compositions of pasteurized Mihaliç cheeses. For this purpose, starter culture combinations consisting of Propionibacterium freudenreichii, Streptococcus thermophilus, Lactobacillus helveticus, and Leuconostoc mesenteroides subsp. cremoris were used. Two scalding temperatures, 40 °C or 45 °C, were used for cheeses with the same culture combination. Samples were evaluated in terms of organic and fatty acid compositions during 90 days of ripening. Eye formation, which is a characteristic feature of Mihaliç cheese, was seen in all cheese samples. Propionic and lactic acids were the most abundant organic acids detected in the cheeses. The most abundant saturated fatty acid was palmitic acid, followed by myristic and stearic acids. Oleic acid content was the highest among total unsaturated fatty acids. The control cheese had lower levels of short-chain fatty acids, which contribute directly to the cheese flavour.

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Equivalent unique global and local initial imperfection is introduced in standards EN 1993-1-1, EN 1999-1-1 in clause 5.3.2 (11) and in Slovak national annex to EN 1993-1-1 NB. 5. However approach described in these standards needs further explanation to fully understand its background to reduce possibility of causing errors. Equivalent unique global and local initial imperfection and derived equivalent unique global and local initial imperfection method is based on obtaining amplitude for structural buckling mode, which can be than used as full-sized imperfection in assessment of structures loaded by combination of axial compression forces and bending moments. Equivalent unique global and local initial imperfection was firstly used and introduced by prof. Eugen Chladný from Slovak University of Technology in Bratislava. The origin of this method was based on the need of assessment of upper chords of open-deck truss bridges. The main idea is described in detail by Prof. Eugen Chladný and Magdaléna Štujberová in paper in magazine Stahlbau vol. 82. Equivalent unique global and local initial imperfection method in mentioned standards and paper is designated for plane structures like simple structural members or frame structures. This paper examines in plane behavior of structures with presented imperfection and calculation procedure, which allows fast examination of many different types of plane structures.

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The chemical composition, fatty acid profile, and cholesterol content of milk fat were analysed during the lactation period of thirty Iranian Ghezel sheep. They were fed dry hay for the first three months and then grazed on fresh grass to the end of lactation, along with barley and wheat middling during the whole period. Fatty acid profile analysis showed palmitic acid to be the dominant fatty acid (45.24±1.88%). During lactation C6:0, C8:0, C10:0, C12:0, and C14:0 contents decreased, while C18:0, C18:1, C18:2, and CLA increased significantly, which can be associated with the change of nutrition from hay to fresh grazing. The cholesterol content of the sheep milk reached 14.88 mg/100 ml milk or 283.43 mg/100 g fat as an average for the whole period of milking. Regression analysis showed a significant increase in cholesterol from 5.42 to 32.87 mg/100 g milk during the lactation period.

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Certain macrofungi species have been used for medical purposes and as nutrients since the old times. The present study aims to determine and compare total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) values, and Fe, Zn, Cu, Pb, and Ni levels in Fomitopsis pinicola (Sw.) P. Karst samples gathered in Balıkesir province Kazdağı National Park and Yalova province Çınarcık Hasan Baba Woods in Turkey. TAS, TOS, and OSI values of mushroom samples were measured with Rel Assay kits. Mushroom heavy metal content was determined using an atomic absorption spectrophotometer and wet decomposition procedure. In the samples collected from Çınarcık district, OSI values were 0.99±0.03, while in the samples collected from Kazdağı National Park, OSI values were 0.13±0.01. Fe content in the samples collected from Çınarcık district were 265.9±70.5 ppm, while Fe content in the samples collected from Kazdağı National Park were 31.31±1.43 ppm. As a result, it is considered that the mushrooms could be used as antioxidant source. Furthermore, it could be argued that as a result of the increase in heavy metal levels, the production of oxidants increases in living organisms, which in turn increases the oxidative stress index.

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Green synthesis of hydroxyapatite (HA) nanoparticles was followed using various concentrations of pectin extracted from the culinary banana bract. The effect of pectin concentrations on purity, crystallinity, particle size, and morphology of synthesized HA nanoparticles were studied. The extracted pectin was characterized by proton-1 nuclear magnetic resonance spectroscopy (1H NMR) and Fourier transform infrared (FT-IR) spectroscopy. FT-IR results revealed that increased concentration (0–0.075 % w/w) of pectin substantially improved the purity level of synthesized HA nanoparticles. In addition, higher concentration of pectin also reduced the crystallinity and size of the synthesized HA nanoparticles, which was confirmed by X-ray diffraction (XRD) and SEM results, respectively. The synthesized HA nanoparticles at increased pectin concentration (HA0.075) evinced high purity, less crystallinity, and discrete uniform shape. Results of TEM images have the credence to reveal the presence of nanosized discrete particles (20–50 nm) with lattice structure of hydroxyapatite.

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The aim of the paper is to investigate the hygrothermal properties of a newly developed building panel, made of ultra-lightweight concrete, encased cold-formed steel elements. It describes the hygrothermal simulations of the wall and roof panels, and based on results, the heat transfer coefficients and linear thermal transmittances are determined. The hygrothermal behavior of main structural joints (wall corner, wall-roof and wall-ground connections) is also simulated using real indoor and outdoor conditions. For validating the results, a model building was investigated.

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Temperature uniformity and heating rate subjected to radio frequency (RF) heating have major impact on the quality of treated low moisture foods. The objective of this paper was to analyse the influence of electrode distance on the heating behaviour of RF on condition that the sample shape, size, and location between the electrodes were defined. Considering peanut butter (PB) and wheat flour (WF) as sample food, a 3D computer simulation model was developed using COMSOL, which was experimentally validated by a RF machine (27.12 MHz, 6 kW). Specifically, the electrode distances were selected as 84, 89, 93, 99 and 89, 93, 98, 103 (mm) for RF heating of PB and WF, respectively. Results showed that the simulated results and experimental data agreed well; the temperature-time histories of the RF heating of PB and WF were approximate straight lines; both the temperature uniformity index and the heating rate decreased with the increase of the electrode distance; the heating rate had a negative logarithmic linear relationship with the electrode distance, which was independent of the types, geometry shapes and sizes of low moisture foods.

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Rapid urbanization has resulted in temperature differences between the urban area and its surrounding areas. Academics have called this as the urban heat island phenomenon. Among the places that have seen rapid urbanization is the City of Cebu. The Philippine’s oldest street, Colon, was chosen as the study area due to the near absence of vegetation and closely spaced buildings. Buildings that are spaced more closely as well as multiple absorptions and reflections produce higher and more viable street temperatures. This study tries to systematically understand the urban heat island effect between Colon and Lawaan, the rural area defined in this study. In order to quantify the urban heat island between two given locations, the mobile traverse method during the summer time, for a 10-day period in May 2016. A digital thermometer measuring platform was mounted on top of a vehicle to measure the different temperatures of Colon Street. Urban temperatures were also gathered in the Lawaan area using the same device. Preliminary results showed the presence of the urban heat island phenomenon between the two areas (ΔT =1.17 °C). The provision of green spaces and proper urban planning are essential in mitigating future urban heat stress due to anthropogenic changes of existing cities.

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Energy saving in buildings is one of the most important research directions in the building sector. Energy saving solutions should not lead to decreased indoor environment quality. Because of the increased number of summer heat waves, cooling systems are widely used to assure thermal comfort in buildings. In this paper, ceiling cooling and wall cooling systems were tested and compared from the thermal comfort point of view using 24 subjects (12 women and 12 men). The cooling ceiling and wall surface and the supply/return temperatures were similar. Analysing the obtained subjective answers, no significant differences were obtained on average or by gender. However, significant differences were obtained between the subjective answers and the calculated PMV values. Furthermore, the occupant’s reaction was different after switching off the ventilation and cooling systems.

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The efficiency and accuracy of the modern positioning systems are crucial points in their design. The designers and engineers are highly motivated to find new methods and solutions to the accuracy problem with the biggest mobility and safety. Considerable numbers of solutions are on the market but only some of them can be used in medical industry. The authors will propose some kinematical simulation methods using MATLAB® software. The purpose of these methods is to use Stewart Platform with a better accuracy. The results show that it is possible to simulate Stewart Platform in MATLAB® and it can be used in medical industry.

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Settling tanks are essential parts of wastewater treatment process and their correct design is therefore crucial for its operation. Modeling of flow in these tanks is difficult, therefore it is necessary to find right tool to perform as precise work as possible. In this article flow velocity measurement in two different secondary settling tanks in Slovakia is presented. Rectangular settling tank in Dolný Kubín and radial settling tank with horizontal flow in Nižná nad Oravou were chosen for this purpose. Data gained from these measurement events will be used for building a model and followed by simulation. Additional data from operation of wastewater treatment plants are also used during the work.

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The lactic acid bacteria are key microorganisms for the production and preservation of fermented dairy products, cheeses, sourdough bread, and lacto-fermented vegetables. This study was developed to monitor lactic acid produced by Lactobacillus plantarum ATCC 8014 and Lactobacillus casei ATCC 393, as single strains and combined, in fermenting media by Fourier Transform Infrared Spectroscopy coupled to multivariate statistical analysis. Media containing different mixtures of carbohydrates were chosen as model fermenting media for monitoring lactic acid concentration by infrared spectroscopy, due to the fact that vegetable and animal food matrices could contain different carbohydrates as carbon sources. Three different types of media were obtained by adding different carbohydrates to a basic MRS medium. HPLC was used as reference method for lactic acid quantification. The calibration set (n=36) was used for building model, while a validation set (n=13) for testing the robustness of the developed model. The coefficients of determination between predicted and reference values were 0.986 and 0.965, while root mean square error for calibration and validation sets recorded values of 0.127 and 0.263 g·l−1, respectively. Results confirmed the efficiency of FTIR spectroscopy combined with multivariate statistics, as a rapid, reliable, and cost-effective tool for routine monitoring of lactic acid.

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The main challenge in any high-speed digital communication system is how to maximize the data rate with minimizing the bit error rate. Several techniques have been developed to achieve this point. Some of these techniques are orthogonal frequency division multiplexing (OFDM), single-carrier frequency domain equalization (SC-FDE), orthogonal frequency division multiple access (OFDMA), and single-carrier frequency division multiple access (SC-FDMA). These four techniques are described briefly in this paper. Also, the paper measures the performances of OFDMA and SC-FDMA systems over international telecommunication union (ITU) vehicular-A channel using minimum mean square error (MMSE) equalization. Simulation results show that the performances with interleaved mapping outperform that with localized mapping. Also, the performances with quadrature phase shift keying (QPSK) are better than that with 16-ary quadrature amplitude modulation (16QAM). In addition, the performance of SC-FDMA is better than that of OFDMA, when QPSK is used, but the latter is little bit better than that of SC-FDMA when 16QAM is used.

Open access
Authors: M. Kopjar, D. Alilović, T. Požrl, V. Piližota and A. Pichler

Sour cherry puree was prepared with addition of sucrose or trehalose (5% and 10%). After stabilization of the mixture (puree with sugars), extracts were prepared and contents of phenolics and anthocyanin, polymeric colour percentage, and antioxidant activity were determined. Extracts were stored for 65 days at 4 °C. Control sample was extract of sour cherry puree without sugars. After extraction, extracts with 10% of sucrose or trehalose had higher phenolic content than the control sample. Anthocyanin content was higher in extracts with trehalose addition. During storage of extracts, samples with trehalose had higher retention of phenolic and anthocyanins than other samples. Addition of sucrose and trehalose as well as their amounts affected the stabilities of phenolics, anthocyanins, and antioxidant activity in sour cherry extracts.

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In this essay work, the ability of probiotic biofilm formation on carrier surface was demonstrated. Probiotic biofilms exhibit the same properties as pathogen microbial biofilms but with higher resistance to low pH values and bile salts. The ability of different probiotic strains (Lactobacillus acidophilus, Bifidobacterium breve, Bifidobacterium longum) to interact with pre-selected carriers divided into 3 categories (polymers, complex food matrices, and inorganic compounds) was tested. Lactobacillus acidophilus and Bifidobacterium longum combined with inorganic silica carrier exhibited the interaction leading to biofilm formation only. Prepared biofilm (Lactobacillus acidophilus) was then subjected to comparative study with planktonic bacterial culture. The ability to survive in the presence of low pH value (pH 1–3) and bile salts (0.3% solution) was evaluated. Low pH value (pH 1) had a harsh effect on free cell culture causing decreased cell viability (71.9±3.2% of viable cells). Biofilm culture exhibited higher resistance to low pH value, the viability exceeded 90%. The exposure of free cell probiotic culture to porcine bile resulted in an almost constant decrease in viability during the study period (68.2±1.1% of viable cells, after 240 min incubation). Viability of biofilm after the exposition to bile was almost constant with a slight decrease of no more than 5% during the study.

Open access
Authors: M. Zheng, Y. Tian, H. Teng, J. Hu, F. Wang, Y. Zhao and L. Yu

In this paper, the wind energy resource in China’s oilfields is analyzed, the difference between China’s energy consumption structure and that of the world in average is analyzed as well, and the application prospect of wind heating technology in China’s oilfields is discussed as an example to reform China’s energy consumption structure. It shows that it is possible to use wind energy as an appropriate heat resource or supplementary heat source in some oilfields to supply heat energy for oil heating and living, more room to improve the energy resource utilization in various fields in China remain. It is a benefit to both oilfield and society to improve energy saving and environments.

Open access

Reconfigurable electronics technology represents a challenging implementation paradigm of actual stage microelectronics. This paper presents the advantages of using hardware reconfigurable microelectronics technology in intelligent spaces development and implementation. An original approach is unfolded which emphasize the versatility of reconfigurable electronic circuit’s topology based configurations in a wide range of intelligent environment applications. The introduced theoretical approaches have been validated then by a real-time intelligent space implementation example. There have been exploited the huge re-routing abilities of reconfigurable electronics associated with its fine-grained operating behaviours. The final result of the theoretical and experimental research efforts is a well-fitted and practical solution for a wide range of intelligent space applications development and implementation.

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The aim of this article is to describe problems of members subjected to biaxial bending and axial compression force and the methods of their design. Members subjected to bending moments about two axes and axial compression force exhibit complex behavior. It is necessary to consider second order theory and imperfections when designing members like that, since they have noticeable influence on resistance in instability. There are examples shown in the article, using methods present in current European standards EN 1993-1-1 and EN 1999-1-1. Attention is drawn to differences in methods, both in applicability and practicality, in design of members with constant and linear bending moment. The purpose of presented paper is to show if the method, which is currently used in Eurocode for aluminum structures, can be also used for steel structures.

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Authors: Brigitta Török, Adél Len and Zoltán Orbán

This paper presents a nonstandard experimental procedure for detection of the presence of salts in building materials. The proposed tests helped modeling the deterioration of specific historical building materials caused by salts. The specimens were subject to visual survey and scanning electron microscope analyses, after submerging them in salt solutions. The results showed the damage of brick, cement based mortar and lime based mortar, caused by various concentrations of sulphate and chloride solutions. By this method various types of salt crystals could be identified. In cement and lime based mortars larger extents of salt deposits were found. A relevant difference between the control samples and the salt treated samples was observed.

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There are several methods for the analysis of road accidents in a road network. In Hungary from 2011 GPS coordinates are used to identify the location of personal injury accidents. This method significantly improves the display of locations of accidents on the map, which can be then analyzed using GIS tools. Accident black spots are the most dangerous places in road networks identified by the density of the accidents in the network. One of the analysis methods is the accident density searching. The methods and algorithms used in some software may show differences in relation to one another. The aim of this research is comparing two applications by investigating the local road network in Győr. The analysis was made using the WEB-BAL accident analysis software using the density-based spatial clustering of applications with noise procedure and the QGIS software using the kernel density estimation method. The former is the official accident database and online software used for accident investigations and the latter is an open source geographic information system. The results are visualized in accident density plots and black spot maps.

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Buildings are the largest consumers of energy, accounting for nearly 40% of all energy used. Therefore, an effective method of reducing energy consumption is to create and design more efficient buildings. In this paper details of a sustainable and green building design for a small residential home are presented. This design is unique in that it is built to Passive house standards, and using shipping containers. The structure will use four 20 ft. (6.1 m) high and one 40 ft. (12.2 m) high cube containers, with the four 20 ft. (6.1 m) making up the main floor and the 40 ft. (12.2 m) forming the second floor. The size is a modest 820 sq. ft. (76.2 m2) designed for a family with one or two children.

The goal for the building is to be as self-sufficient as possible which makes it ideally suited to an ‘off-grid’ rural setting. However, it can be adapted to be ‘on-grid’ as well. Solar energy will provide all the electricity needs through a photovoltaic battery system, and warm water with a solar water heater. The site will be water neutral by utilising rainwater harvesting and on site waste water treatment. The results from energy modelling, using HOT2000, are presented, as well as an in-depth analysis on different insulation types and strategies. Finally, a cost estimate exercise is conducted and results compared to other passive houses and traditional code compliance buildings.

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The primary aim of the paper is to present a simple method for determining the changes in stiffness of a composite beam. The experimental model was made from wood and plaster boards. It was simply supported beam with a length of 4 m. Accelerations were measured at 24 points along the beam. In either case data for intact and damaged models were acquired. The identification of the damage was done using a code developed by the authors. The vertical mode-shapes were analyzed, so changes in the stiffness could be detected.

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Milk and dairy products are high-value foods; however, consumers suffering from lactose intolerance are not able to enjoy the nutritional benefits of these commodities. There are more and more researches and developments focusing on lowering the lactose content of milk and dairy foods in order to make them available for lactose intolerant people. In this study, we examined the coagulation time, product quality, texture profile properties, and syneresis of yoghurts prepared from lactose-free milk. Significant differences were observed between the control and lactose-free milks with respect to coagulation time and texture profile. The first rupture time, the hardness, and the adhesion force of the lactose-free yoghurt were higher compared to the control product. We observed remarkable difference between the whey leakage of control and lactose free yoghurt samples (21.47% and 14.63%). Results coming from instrumental texture profile analyses showed that the preliminary lactose hydrolysis of milk resulted a firmer texture. It was confirmed by the results of sensory evaluation, and considering the texture and taste, there was significant difference between the control and lactose-free yoghurts.

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In an attempt to devise a model which more closely imitates cellular biology a three-dimensional (3D) artificial organism model developed upon a two-layer coarse-fine-grid network model is proposed in this paper. The strength of this original approach is that it endeavors to capture the complexity of both the cellular networks as well as that of the biological cell itself, by implementing the internal biological phenomena of an organism into a 3D two different network topology hardware layer. In essence, this model not only keeps the full advantages of previously created 2D models that enable the implementation of similar self-replicating or selfrepairing abilities akin to those expressed by its cellular equivalents in nature, but there the inherent need of artificial cell structures to fulfill the entire role of a biological cell in the network is also expressed. Computer-aided simulation results prove that this kind of 3D coarse-fine-grid approach is well feasible physically therefore the model has been implemented into a computing platform made of custom reconfigurable Field Programmable Gate Array (FPGA) processors.

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Several cities in the country have experienced the rapidly-growing period for more than two decades. New technologies are playing an important role in the green building performance encouraging new architects, engineers and investors in choosing ecological materials. Referring to the European Commission and building codes, recent regulations of local plans for various municipalities emphasize in particular the environmental improvements in urban areas, especially areas with cultural heritage. The scope of this study is to highlight the wood applications as a green material for the construction/restoration phase in residential buildings, dwellings, interior spaces, façades and multifunctional buildings in the urban environment.

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The wettability of a copper substrate by Sn–Ni alloy and the interfacial active properties of nickel were investigated. We determined the contact angle as a function of holding time in the Sn–Ni/Cu system at low Ni concentration. The contact angle of Sn can be decreased from 30° to 25° by adding 0.1 wt% Ni to Sn. We observed accumulation of the nickel at the solid–liquid interface. We assume that the nickel accumulation is caused by the interfacial active property of the nickel in an Sn–Ni/Cu system.

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Authors: Haroune Rachid Ben Zine, Filiz Cinar Sahin, Zsolt E. Horváth, Zsolt Czigány, Ákos Horváth, Katalin Balázsi and Csaba Balázsi

The effect of the submicrometer-sized Si3N4 addition on the morphological and structural properties of the ceramic dispersion strengthened (CDS) 316L stainless steels prepared by powder technology has been studied. Two composites were prepared: 316L/0.33 wt. % Si3N4 and 316L/1 wt. % Si3N4. In order to assure a good dispersion of the ceramic particles in the stainless steel powders and a grain size reduction at the same time, the high efficient attrition milling has been used. Spark plasma sintering (SPS) was used for fast compacting of milled composites. Structural and morphological changes were studied after milling and sintering process. It was found that the amount of Si3N4 addition influenced the efficiency of milling process resulting in powder mixtures with different 316L stainless steel grain size and shapes. In the case of 0.33 wt. % Si3N4 addition, the flat 316L stainless steel grains with submicrometer size in thickness have been resulted after milling compared to 1 wt. % Si3N4 added powder mixtures which consisted of almost globular 316L stainless steel grains with 50–100 μm in diameter. The intensive milling assured an optimal coverage of 316L stainless grains with Si3N4 submicrometer-sized particles in both cases as demonstrated by energy dispersive spectroscopy (EDS) and TEM. On the other hand, the 316L phase has been maintained during and after the milling and sintering. The partial phase transformation of α-Si3N4 to SiOx was observed by EDS.

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The aim of this article is to study the influence of TiC/a:C protective thin film on the corrosion and mechanical properties of sandblasted/polished Ti and TiAl6V4 substrates. The electrochemical corrosion behaviors of the samples were investigated in simulated body fluid (SBF) by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques at 7.4 pH and 37 °C. The metal ion release has been quantified by inductively coupled plasma optical emission spectroscopy (ICP-OES). The experimental results obtained from different electrochemical methods, ICP-OES, and scanning electron microscopy (SEM) showed that the TiC/a:C protective coating on sandblasted implant device improves the corrosion properties of the implant material and it is able to control the metal ion release. It was also shown that the hardness of the bare implant materials is improving by four orders of magnitude with the TiC/a:C nanocomposite coating beside a moderate elastic modulus value. The highest hardness (H) of ~28 GPa ± 3 was observed in the case of the film prepared at ~38 at% Ti content. Overall, the TiC/a:C thin film has suitable electrochemical characteristics for further consideration and assessment as a protective coating.

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Authors: Judit Babcsán, Shai Essel, Nahum Karni, György Számel, Sándor Beke and Norbert Babcsán

Aluminum foams have low density, high energy absorption, and specific stiffness. Further strengthening of aluminum foam-based structures can be achieved by using a massive metallically bonded outer aluminum shell. Thanks to Aluinvent aluminum foaming technology and the developed casting processes, we can produce such parts with different shape, size, and controlled mechanical properties. Thus, aluminum foams and complex cast around structures with aluminum foam core are excellent candidates of cast three-dimensional (3D) shape car parts. Using micro-computed tomography (μ-CT) investigation in this study, we demonstrate that the developed aluminum foam cored high-pressure die cast around prototypes are having well controlled metallic bond and, during the casting process, the liquid aluminum penetrates in a controlled manner into the outer bubble layer of the solid aluminum foam.

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Authors: Szilvia Ormándi, Ildikó Cora, Zsolt Dallos, Ferenc Kristály and István Dódony

Zeolites are crystalline microporous alumosilicates whose unique pore and channel systems are the reason for their important role in catalysis, separation, and ion exchange. This work focuses on the morphology and structure of a natural zeolite, mordenite. Our samples were collected at Lengyendi-galya (Gyökeres-tető) in the Mátra Mountains (NE-Hungary). Zeolite samples were investigated by X-ray powder diffraction, scanning, and transmission electron microscopy. Mordenite has typically fibrous appearance and occurs in association with other zeolites such as heulandite and chabazite. Based on intense streaks and superlattice reflections in selected area electron diffraction patterns, we identified planar faults in the structure. A single fault produces a dachiardite-type structural slab within the mordenite lattice, reducing its channel size.

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Damage induced on soybean by Tetranychus urticae Koch (Acari: Tetranychidae) is easily recognizable. We were curious to know whether, in addition to this visual and quantitative damage, change occurs also in the nutritional value of the harvested product.

The Weendei analysis showed that as compared to the healthy items, the protein content (P=0.048) of the miteinjured seeds as well as their composition (P=0.048) has changed. No significant changes in the raw fat content could be confirmed by the statistical results of the study (P=0.643). Concerning the contents of raw ash (P=0.069) and raw fibre (P=0.859), there were no significant differences.

Three distinct changes in protein structure were confirmed by gel electrophoresis. Substantially less 69 kDa protein was detectable in the infested soybean, whereas no 48 kDa protein was present in the control sample; it only appeared in the infested ones. There was a higher amount of 30 kDa protein in the infested stock. In summary, alteration in the protein structure was caused by T. urticae, and changes were triggered in the protein content of the affected soybean plants. The protein structure-change in damaged soybean items caused further decline in the feed consuming capacity of farm animals.

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The aim of the study was to determine and compare the collagen profile of two beef carcass cuts: silverside (M. semitendinosus) and strip loin (M. longissimus lumborum), originated from Polish Holstein-Friesian bulls of the black and white variety. Silverside showed higher total, acid-soluble, total soluble, and insoluble collagen content than strip loin. Significant differences between silverside and strip loin were noted in their share of water-soluble and acid-soluble collagen (% total collagen, P<0.05). The thermal treatment caused cooking losses, which reached 38% in strip loin and 40% in silverside. There were no significant differences in shear force values or organoleptic quality between the cuts, which indicates their similar usefulness as meat for roasting. The content and profile of intramuscular collagen did not influence the organoleptic quality or shear force values of silverside and strip loin.

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Revealed comparative advantages are widely used by the global literature to analyse international trade flows, though agricultural trade is usually neglected in empirical works. Moreover, the determinants of revealed comparative advantages are scarcely investigated. This article analyses revealed comparative advantages in European Union’s cheese trade from 1990 to 2013 and identifies its determinants by using panel data econometrics. Results suggest that GDP/capita, geographical indication, and EU membership are positively, while foreign direct investment (FDI) is negatively related to revealed comparative advantages.

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Authors: N. Hromiš, B. Šojić, V. Lazić, N. Džinić, A. Mandić, V. Tomović, S. Kravić, S. Škaljac, S. Popović and D. Šuput

The aim of this paper was to examine the effect of chitosan coating with the addition of caraway essential oil and beeswax on lipid oxidation protection, as well as aroma and water content preservation of traditional dry fermented Petrovská klobása sausage.

During the entire storage period, TBARS index value in coated sausage was lower compared to the control (P<0.05). After two months of storage, TBARS index value in control and coated sausages were 0.94±0.04 mg kg–1 and 0.66±0.03 mg kg–1, while after seven months of storage, these values were 0.82±0.05 mg kg–1 and 0.67±0.02 mg kg–1, respectively. While content of saturated aliphatic aldehydes increased in control sausage (P<0.05), it remained unchanged in coated sausage during 7 months of storage. Lipid oxidation protective effect could be correlated to higher marks for aroma of coated sausage during the entire storage period (P<0.05). Coating slowed moisture loss of coated sausage compared to the control (P<0.05).

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The influence of storage time on different quality parameters and in vitro antioxidant activity of peaches cv. Elegant Lady harvested at two ripening stages (immature and commercial mature) and stored under cold and marketing conditions were assessed. Destructive (physical-chemical properties, antioxidant activity, and firmness) and non-destructive parameters (colour and index of absorbance difference, IAD) were assessed.

Storage and ripening stage influenced firmness, colour, and antioxidant activity. Firmness decreased significantly during cold and marketing storage, and skin colour parameters, a* and b*, underwent a deepening of the red hue, while IAD values fully justified differences in colour over storage time and ripening stage. The antioxidant activity increased during storage, although polyphenols and ascorbic acid contents remained constant, and was higher in commercial mature fruit than immature peaches, that revealed a ratio of total sugars/total acids more equilibrated.

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Turkey’s and several Middle East countries’ people consume “leblebi”, which is a traditional snack food made from chickpea (Cicer arietinum L.). Leblebi processing steps caused significant decrease (P<0.05) in moisture and carbohydrate fractions. The dietary fibre contents were also reduced through leblebi processing steps. Dehulling process caused reduction in cellulose from 2.6 to 1.3%, whereas increase in acid detergent lignin content from 0.27 to 0.85% was observed. The mineral analysis results have shown that leblebi samples supply macro and micro nutrients required in the human diet.

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High levels of peptides can accumulate in tissues of legumes during germination. In this study, effects of germination conditions (pH, temperature, and time) on protease activity and peptides accumulation in soybean were investigated. The desirable level scope of parameters was used to further optimise germination conditions for peptides accumulation using response surface methodology. Results showed that protease activity and peptides yield were significantly influenced by pH, temperature, and time (P<0.05). The optimal pH, temperature, and time for protease activity were 5, 25 °C, and 6 days, respectively. Meanwhile, the optimal pH, temperature, and time for peptides content were 5, 30 °C, and 5 days, respectively. Box–Behnken design indicated the following optimal germination conditions: pH 4.8, temperature 29 °C, and time 5 days. Under these conditions, the highest peptides content (14.46 mg g–1 FW) in germinated soybean was obtained. The present study indicates that germinated soybean can be a valuable component of peptides-enriched foods.

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Lactic acid bacteria were isolated from tungrymbai, a traditional fermented soybean product of Meghalaya, India and assessed for their probiotic properties. Survival under simulated gastric conditions was tested and five acid tolerant strains were selected. By using 16S rDNA sequencing, these isolates were confirmed to be Enterococcus species. The strains exhibited good survivability in high concentrations of bile salts. The strains were susceptible to antibiotics and they were also found to inhibit growth of Staphylococcus aureus and Escherichia coli. The strains were gelatinase negative and non-haemolytic. The strains also assimilated cholesterol up to a certain level. The study confirmed that all identified five strains have in vitro probiotic properties.

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Authors: R.T. Mócsai, A. Maczó, C. Grünwald-Gruber, K. Majer-Baranyi, N. Adányi, P. Milotay, J. Czelecz and R. Tömösközi-Farkas

Investigation of putative allergens from tomato berries is challenging as differences between human serum IgE specificity and reactivity as well as the non-specific binding of the primary and secondary antibodies often cause difficulties. In this study five tomato cultivars were investigated to evaluate their potential allergenicity in Hungarian tomato sensitive patients. The major allergens proved to be low molecular weight proteins, but several previously described allergens could be identified as well using IgE-Western blotting. IgE binding to cross-reactive carbohydrate determinants (CCDs) was ruled out through the use of CCD inhibitor, but non-specific binding of the secondary antibody remained an issue. IgE binding activity of a purified, immunoblot positive protein (band at 40 kDa), and non-specific binding of the secondary antibody to the same protein, was demonstrated with an Optical Waveguide Lightmode Spectroscopy (OWLS) based immunosensor. LC-ESI-MS/MS analysis showed this protein is an as-yet undescribed vicilin-type putative allergen.

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With the aim to determine the influence of packaging in preserving the quality of wine, in this research project the chemical and sensorial evolution of a red wine stored in different packaging materials (glass bottles vs multilayer Tetrabriks®) has been evaluated over a period of 12 months. Furthermore, two different temperature levels (4 and 20 °C) for each packaging solution were maintained throughout the storage period.

The results show how the characteristics of packaging could deeply affect wine quality as a function of the storage conditions used, and suggest that with their rational optimization the quality of red wine during storage can be kept and its shelf life extended. In this context, the kinetic characterization of the time evolution of some chemical compounds that can be assumed as indexes of wine oxidation rate could enhance the consumer’s enjoyment during tasting.

Under the adopted experimental conditions, the rate of wine aging was higher when the storage temperature increased. Furthermore, after 12 months of storage at room temperature, the glass bottles generally better preserved red wine from oxidation than multilayer Tetrabriks®.

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Coeliac disease (CD) is an autoimmune, gluten-related disorder occurring in genetically predisposed individuals. The keystone to CD management is a gluten-free diet (GFD). Recently, media have been promoting the application of a GFD, however, this is necessary only in gluten-related disorders. The aim of the present study was to evaluate the knowledge on CD among individuals, who conducted a self-administered coeliac disease test. Three hundred adult volunteers took part both in the anti-tissue transglutaminase screening and the survey concerning knowledge on CD. Five positive CD tests were obtained, representing 1.67% of the analysed population. In general, the questionnaire respondents were familiar with the issue of CD. The majority of them correctly defined CD as gluten intolerance, and realized that it may occur at any age. Gastrointestinal problems were easily associated with CD, however, extraintestinal symptoms were less frequently recognized as a manifestation of this disease. A GFD was properly identified as a method of treating CD by 95% of the respondents. Self-administered, transglutaminasebased screened persons presented a good level of knowledge on CD, regardless of their gender, place of residence, or education. However, dissemination of knowledge is needed, as CD is still an underestimated problem.

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We used an alternative approach, loop-mediated isothermal amplification, to detect Mangalitza component in food products, and it has been compared to an established Recombinase Polymerase Amplification test. The correlation between the assays was significant (P<0.01). Linear determination coefficient between the assays was 0.993 and level of diagnostic agreement was high (Kappa=0.971).

Previously, a real-time PCR method based on TaqMan probe was developed (Szántó-Egész et al., 2013) for detection of Mangalitza meat in food products, using a Mangalitza specific sequence. Other Mangalitza specific sequences suitable for the same purpose are also in use (V. Stéger, personal communication).

Approaches like real-time monitoring of accumulation of the specific DNA product usually require specialised laboratory equipment. For Mangalitza detection, portable Recombinase Polymerase Amplification (RPA) approach has been developed (Szántó-Egész et al., 2016), which requires a device capable of maintaining 39 °C and a lateral flow strip with easy yes/no indication of the successful amplification.

We wanted to develop another fast, non-PCR based test with minimal laboratory requirement to provide a third possibility to detect Mangalitza component in food.