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Found 6674 publications
Relationship between total cell counts and exopolysaccharide production of Streptococcus thermophilus T9 in reconstituted skim milk
Publication Name: Lwt
Publication Date: 2021-08-01
Volume: 148
Issue: Unknown
Page Range: Unknown
Description:
The main objective of this study was to establish a correlation between total bacterial count (TBC) and exopolysaccharide (EPS) production in a specific Streptococcus thermophilus strain. TBC was determined based on real-time quantitative polymerase chain reaction (qPCR) standard curves of S. thermophilus T9 cultured in reconstituted skim milk. EPS yields were measured following isolation and purification steps using a dextran standard curve. The relationship between TBC of and EPS production by S. thermophilus T9 was analyzed alongside these standard curves. The results showed that EPS yield reached 36.6 ± 0.8 mg L−1 following 6 h of incubation. Over the same period, the streptococcal counts measured by qPCR increased from 4.71 ± 0.15 to 7.52 ± 0.09 log10 TBC mL−1. Overall, EPS biosynthesis has been shown to be a growth-related trait in S. thermophilus T9 (R2 = 0.991). In conclusion, the monitoring of TBC may provide an insight into the mechanism of EPS production and, therefore, its use can be recommended for this purpose and for EPS quantification. To our knowledge, this is the first research that has associated qPCR-based TBC with EPS yield in S. thermophilus.
Open Access: Yes
Effect of Chemical Composition of Clay on Physical-Mechanical Properties of Clay Paving Blocks
Publication Name: Buildings
Publication Date: 2022-07-01
Volume: 12
Issue: 7
Page Range: Unknown
Description:
Clay paving blocks made of natural, environmentally friendly materials have their own originality and colorful authenticity, but due to the complex technological production process, they are also relatively expensive products; therefore, their environmental resistance properties are strictly defined and controlled by the standards. The physical and mechanical properties of clay paving blocks are the key factors aiming to ensure the longevity of products and their long-term success in the market. Therefore, ensuring high physical and mechanical properties of clay paving blocks have become a most crucial challenge for the manufactures. This article considers the parameters of the technological production process of clay paving blocks manufacturing and evaluates the influence of the chemical composition of three different types of clay on the physical and mechanical properties of the paving blocks. Water absorption, linear shrinkage, freeze/thaw, acid resistance, and transverse breaking load of clay paving blocks are investigated. This study reveals the importance of raw material selection in the production process of clay paving blocks and provides the concept of main quality factors of clay.
Open Access: Yes
Selection of Heat Transfer Enhancement Technique for Compact Mini and Micro Heat Exchangers Design
Publication Name: Chemical Engineering Transactions
Publication Date: 2025-01-01
Volume: 120
Issue: Unknown
Page Range: 475-480
Description:
The need to decrease the sizes and masses of heat exchangers while preserving their performance has stipulated the development of compact heat exchangers with mini and micro channels (MCHE). It is supported by the need for increased recuperation of heat energy, facilitating better energy efficiency with strict limitations for space, material and cost. The adequate substitution of conventional heat exchangers with MCHE requires maintaining the same heat load, not exceeding the allowable pressure losses. The different ways to increase the compactness are analysed, including the change of hydraulic diameter, and the use of various methods of heat transfer intensification by changing the channel geometry and flow structure. The Nusselt numbers and friction factors correlations for plane tubes and criss-cross flow channels of plate heat exchangers are compared. A newer form of the core velocity equation has been developed, which allows comparison of the performance of MCHE heating surfaces with different enhancement techniques in specific process conditions. The results of the calculations illustrate the influence of the channel's hydraulic diameter and length on the MCHE performance for channels with the considered methods of heat transfer intensification. The ways to decrease channel size to mini and micro scales are determined. The recommendations on choosing the best channel geometry and size, depending on specified process conditions and stream nature, are formulated.
Open Access: Yes
DOI: 10.3303/CET25120080
TP Transformation of the Inverted Pendulum
Publication Name: Gpmc 2020 2nd IEEE International Conference on Gridding and Polytope Based Modeling and Control Proceedings
Publication Date: 2020-11-19
Volume: Unknown
Issue: Unknown
Page Range: 13-18
Description:
This paper describes a Tensor Product (TP) based model via the inverted pendulum. Base of the controller designing is used the Linear Matrix Inequality (LMI) in order to stabilize the nonlinear system. This case shows the quasi-Linear Parameter-Varying (qLPV) modeling and the Higher-Order Singular Value Decomposition (HOSVD) based TP transformation.
Open Access: Yes
Impact of environmental and soil factors in the prediction of soil carbon dioxide emissions under different tillage systems
Publication Name: Ecocycles
Publication Date: 2022-01-01
Volume: 8
Issue: 1
Page Range: 27-39
Description:
Understanding the roles of natural drivers in greenhouse gas (GHG) emissions of arable fields is crucial for adequate agricultural management. This study investigated the combined effect of two tillage treatments (NT - no-tillage; CT - tillage with mouldboard ploughing) and environmental (air pressure, air temperature) and soil factors (total organic carbon, gravimetric water content and soil penetration resistance) on soil carbon dioxide (CO2) emissions in maize in 2020 and 2021. The soil tubes required for the laboratory measurement were derived from three different altitudes of the two differently cultivated fields from Fejér county, Hungary. The typical soil type was Chernozem in both fields. At the time of soil sampling, soil penetration resistance was measured with a 06.15SA Penetrologger in 10 repetitions. To preserve the moisture content of the soil columns during the investigation, moisture replenishment was performed equal to the degree of weekly theoretical evapotranspiration. Emissions measurements of soil columns were performed by close chamber technique for five weeks from sampling, 15 times, in 3 repetitions in laboratory conditions. The data were evaluated by two-way ANOVA, followed by the Tukey HSD multiple comparison test and two-tailed Student's T-test at a significance level of p<0.05. The combined effect of environmental factors on soil carbon dioxide emissions was investigated using stepwise multiple linear regression. It has been proved that the observed difference between soil penetration resistance and soil carbon dioxide emissions was significant between CT and NT cultivation at different stages of the growing season. The analysis of the interaction of the experimental factors revealed that the combined effect of soil penetration resistance, total organic carbon and moisture content in tillage system (adjusted R2=0.92 at a significance level of p=0.05) in 2020, while the combined effect of moisture content and air temperature in the no-tillage system (adjusted R2=0.79 at a significance level of p=0.085) has the most significant effect on soil CO2 emissions in 2020. In 2021, the air temperature for the tillage system (adjusted R2=0.74 at a significance level of p=0.05) and the combined effect of air temperature and pressure for no-tillage systems (adjusted R2=0.69 at a significance level of p=0.1) played an important role in soil CO2 emissions. These observations highlight that different soil and environmental factors of different tillage significantly impact the soil carbon dioxide emissions in different years.
Open Access: Yes
Risk of pneumonia during adalimumab therapy
Publication Name: Orvosi Hetilap
Publication Date: 2026-03-01
Volume: 167
Issue: 12
Page Range: 466-475
Description:
Bridging steroid therapy given in addition to adalimumab-methotrexate dual therapy which was introduced for autoimmune diseases notably contributes to the increased risk of pneumonia. Authors review the international literature and evaluate the incidence of pneumonia caused by adalimumab monotherapy, adalimumab-methotrexate dual therapy, and adalimumab-methotrexate-steroid triple combination therapy, as well as steroid tapering protocols. They go into the importance of effective adalimumab levels recommended for each clinical picture and the measurement of anti-adalimumab antibodies, which is part of the precision medicine for autoimmune diseases. These laboratory tests help to identify the causes of steroid dependence and show the direction how to achieve a steroid-free status, thereby the risk of pneumonia in treated patients could be reduced. Orv Hetil. 2026; 167(12): 466–475.
Open Access: Yes
Investigation of the Effects of Thermit Welding on the Mechanical Properties of the Rails
Publication Name: Acta Polytechnica Hungarica
Publication Date: 2022-01-01
Volume: 19
Issue: 3
Page Range: 37-49
Description:
This current paper deals with the investigation of the variation of the hardness of the rail steel material in the heat-affected zone (HAZ) of a rail joint made by thermit welding (TW). The tested rail is a normal R260 type rail steel category; its production date is 1977, the rolling mill was Diosgyor (Hungary), rail profile is MÁV 48.5. This rail has not been in railway track before the test. The authors performed hardness tests on the rail head’s surface even after the rail welding, as well. After the welding and hardness tests, the rail joint was cut with +/–200 mm by a rail cutter and transported to the laboratory. Water jet cutting was applied to shape six longitudinal direction slices with five vertical cutting lines from the rail piece’s head. The slices’ length was 400 mm, the width of these slices was approx. 10 mm; the TW rail joint was in the mid-point of the slices. Micro-Vickers (HV10) hardness tests were executed on these slices, in the –150…+150 mm interval lengthwise and in the 3, 6, and 10 mm depth points below the rail head’s top surface. As a result, the authors received a very detailed hardness functions of the HAZ of rail joint made by TW. These variation functions were compared to the official Elektrothermit’s SoW-5 hardness tests’ results. It can be concluded that the variation of the hardness of rail steel in the area of the HAZ correlated with the Elektrothermit’s results; however, there were some critical points where significant differences were able to be found. The highest deviation was concluded in 50 mm distance measured from the axis of welded rail joint. The authors gave possible valuable explanations for these phenomena.
Open Access: Yes
DOI: DOI not available
The Role of Micronutrients to Support Immunity for COVID-19 Prevention
Publication Name: Revista Brasileira De Farmacognosia
Publication Date: 2021-08-01
Volume: 31
Issue: 4
Page Range: 361-374
Description:
The World Health Organization declared the novel coronavirus, named as SARS-CoV-2, as a global pandemic in early 2020 after the disease spread to more than 180 countries leading to tens of thousands of cases and many deaths within a couple of months. Consequently, this paper aims to summarize the evidence for the relationships between nutrition and the boosting of the immune system in the fight against the disease caused by SARS-CoV-2. This review, in particular, assesses the impact of vitamin and mineral supplements on the body’s defence mechanisms against SARS-CoV-2. The results revealed that there is a strong relationship between the ingestion of biological ingredients like vitamins C–E, and minerals such as zinc, and a reduction in the effects of coronavirus infection. These can be received from either nutrition rich food sources or from vitamin supplements. Furthermore, these macromolecules might have roles to play in boosting the immune response, in the healing process and the recovery time. Hence, we recommend that eating healthy foods rich in vitamins C–E with zinc and flavonoids could boost the immune system and consequently protect the body from serious infections. Graphical Abstract: [Figure not available: see fulltext.].
Open Access: Yes
Evaluating the effect of a brewery by-product as feed supplementation on the quality of eggs by means of a human panel and e-tongue and e-nose analysis
Publication Name: Chemosensors
Publication Date: 2021-08-01
Volume: 9
Issue: 8
Page Range: Unknown
Description:
The objective of our research was to evaluate the possible alteration of the organoleptic properties of eggs produced by hens (Lohmann Brown-Classic) fed with diets containing different doses of an industrial by-product enriched with organic zinc (Zincoppyeast, ZP): Control 0%, ZP 2.5%, and ZP 5.0%. Eggs were collected after 30 days (batch 1) and 60 days (batch 2) of feeding with the experimental diets and subjected to chemical, microbiological, human sensory, e-nose, and e-tongue analyses. There was no significant difference among the microbiological status of eggs of the three groups, but there were significant differences (p < 0.05) in the fat (9.5% vs. 9.3%) and protein contents (12.7% vs. 13.4%) of the Control and ZP 5.0% groups, respectively. Human sensory analysis showed no clear change in the organoleptic characteristics of the eggs. Using linear discriminant analysis (LDA), the e-tongue could recognize the three groups of eggs in batch 1 and batch 2 with 95.9% and 100% accuracy and had a prediction accuracy of 64.8% and 56.2%, respectively. When the eggs were incubating at 50 °C or 80 °C before the e-nose analysis, the groups of eggs could be recognized with 98.0% and 82.7% accuracy, and predicted with 68.5% and 62.2% accuracy, respectively, using principal component analysis-based discriminant analysis (PCA–DA). The aroma compounds and respective sensory descriptors showing changes among the different groups of eggs (batch, storage, and feeding) were identified based on the e-nose analysis. The sup-plementation of laying hens’ feed with the investigated industrial by-product can be applied without any substantial effect on egg quality, which can, however, be detected with advanced analytical methods.
Open Access: Yes
