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Publications - 6374

Correction to: Deindustrialization, Tertiarization and Suburbanization in Central and Eastern Europe. Lessons Learned from Bucharest City, Romania (Land, (2023), 12, 9, (1731), 10.3390/land12091731)

Tamás Hardi Radu Săgeată Ines Grigorescu Bianca Mitrică Andreea Loreta Cercleux

Publication Name: Land

Publication Date: 2024-04-01

Volume: 13

Issue: 4

Page Range: Unknown

Description:

In the original publication [1], there was a mistake in the legend for Figure 1 and Figure 4. A map legend can be explained either by text within the figure (where space permits) or by numbering the conventional signs within the figure, and explaining them below the figure (where space is more limited). In Figure 1 and Figure 4, the second method of explanation was initially used (by means of the numbers explained under the figure), but later, according to the indications received from the referents, the numbers in the figures were replaced by their explanations (according to the version uploaded on 3 September 2023). Due to an unfortunate error, in the version uploaded on 6 September 2023, Figure 1 and Figure 4 were uploaded with the conventional numbered signs in the legend, but without the explanation of the numbers below the figure, making the figures much more difficult to explain. Therefore, we request that these two figures be replaced with their variant, where the legend is explained in the text, as indicated by the referents. The correct legend appears below. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.

Open Access: Yes

DOI: 10.3390/land13040486

Optimising Portfolio Risk by Involving Crypto Assets in a Volatile Macroeconomic Environment

Gergő Thalmeiner László Pataki Attila Bányai Tatay Tibor

Publication Name: Risks

Publication Date: 2024-04-01

Volume: 12

Issue: 4

Page Range: Unknown

Description:

Portfolio diversification is an accepted principle of risk management. When constructing an efficient portfolio, there are a number of asset classes to choose from. Financial innovation is expanding the range of instruments. In addition to traditional commodities and securities, other instruments have been added. These include cryptocurrencies. In our study, we seek to answer the question of what proportion of cryptocurrencies should be included alongside traditional instruments to optimise portfolio risk. We use VaR risk measures to optimise the process. Diversification opportunities are evaluated under normal return distributions, thick-tailed distributions, and asymmetric distributions. To answer our research questions, we have created a quantitative model in which we analysed the VaR of different portfolios, including crypto-diversified assets, using Monte Carlo simulations. The study database includes exchange rate data for two consecutive years. When selecting the periods under examination, it was important to compare favourable and less favourable periods from a macroeconomic point of view so that the study results can be interpreted as a stress test in addition to observing the diversification effect. The first period under examination is from 1 September 2020 to 31 August 2021, and the second from 1 September 2021 to 31 August 2022. Our research results ultimately confirm that including cryptoassets can reduce the risk of an investment portfolio. The two time periods examined in the simulation produced very different results. An analysis of the second period suggests that Bitcoin’s diversification ability has become significant in the unfolding market situation due to the Russian-Ukrainian war.

Open Access: Yes

DOI: 10.3390/risks12040068

The historical role of milk and dairying in shaping European societies

László Varga

Publication Name: Elelmiszervizsgalati Kozlemenyek

Publication Date: 2017-06-30

Volume: 63

Issue: 2

Page Range: 1537-1547

Description:

Based on results recently published in the scientific literature, the author briefly outlines in this mini-review how dairying has become, over thousands of years, a basic activity of humankind. Following the domestication of cattle, goats and sheep, which had begun approximately 10,500 to 11,000 years ago in the Middle East, milk was already in use in northwestern Anatolia by the seventh millennium BC. In lack of lactase, however, milk consumption resulted in unpleasant outcomes (e.g., flatulence, cramps, diarrhea, etc.) in the vast majority of prehistoric farmers. The negative symptoms associated with lactose intolerance were later considerably alleviated by the introduction of simple milk processing techniques such as fermentation. Thus, for instance, Neolithic farming communities in north-central Poland started producing cheese between 6800 and 7400 years ago. Intriguingly, the ability to digest lactose in adulthood, termed lactase persistence (LP), emerged as a result of a genetic mutation at about the same time in central Europe, and the LP allele has been subject to strong positive selection afterwards. As the so-called gene–culture coevolutionary model suggests, the cultural evolution of dairy farming tightly entwined with the biological evolution of LP over millennia, and these processes are likely to have profoundly influenced the genetic composition of European populations.

Open Access: Yes

DOI: DOI not available

Comparative study on credibility measures of type-2 and type-1 fuzzy variables and their application to a multi-objective profit transportation problem via goal programming

Dipak Kumar Jana Palash Sahoo Laszlo T. Koczy

Publication Name: International Journal of Transportation Science and Technology

Publication Date: 2017-06-01

Volume: 6

Issue: 2

Page Range: 110-126

Description:

In real world applications supply, demand and transportation costs per unit of the quantities in multi-objective transportation problems may be hardly specified accurately because of the changing economic and environmental conditions. It is also significant that the time required for transportation should be minimized. In this paper, we have presented three reduction methods for a type-2 triangular fuzzy variable (T2TrFV) by adopting the critical value (CV). Three generalized expected values (optimistic, CV and pessimistic) are derived for T2TrFVs with some special cases. Then a multi-objective profit transportation problem (MOPTP) with fixed charge (FC) cost has been formulated and solved in type-2 fuzzy environment. Unit transportation costs, FC, selling prices, unit transport times, loading and unloading times, total supply capacities and demands are all considered as triangular Type-2 fuzzy numbers. The MOPTP has been converted into a single objective by using the goal programming technique and the weighted sum method. The deterministic model is then solved using the Generalized Reduced Gradient method Lingo 14.0. Numerical experiments with some sensitivity analysis are illustrated the application and effectiveness of the proposed approaches.

Open Access: Yes

DOI: 10.1016/j.ijtst.2017.06.002

Adoptive T-cell therapies for persistent COVID-19 in immunocompromised patients: Comparison of IFN-γ virus-specific T-cell therapy and CD45RA+ T-cell depleted donor lymphocyte infusion

Dóra Mathiász Nóra Meggyesi János Sinkó Gabriella Bekő Botond Lakatos Andrea Ceglédi Hajnalka Andrikovics István Vályi-Nagy Bálint Gergely Szabó Szabolcs Tasnády Borisz Rabán Petrik Judit Bogyó Katalin Dobos Laura Giba-Kiss Orsolya Kis Gottfried Miskolczi Noémi Németh Ilona Bobek László Gopcsa János Szlávik Péter Reményi Marienn Réti Zsuzsanna Várnai Anikó Szilvási

Publication Name: Geroscience

Publication Date: 2026-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Advanced age, comorbidities, and immunocompromised states remain major risk factors for severe or persistent COVID-19 despite vaccination and antivirals, underscoring the need for innovative treatments such as adoptive T-cell therapy (ATT). In this prospective single-center study, we evaluated the safety, feasibility, and efficacy of two ATT approaches in immunocompromised patients with high-risk or persistent SARS-CoV-2 infection: interferon-γ cytokine capture system virus-specific T cells (IFN-γ CCS VST, n = 12; median age 59) and CD45RA + T-cell depleted donor lymphocyte infusion (CD45RA+ TCD DLI, n = 11; median age 46). Most patients (73.9%) had undergone prior hematopoietic stem cell transplantation (HSCT). Both treatments were safe, with no adverse events observed. One-year overall survival (OS) did not differ significantly between groups (p = 0.8907 overall; p = 0.5907 in HSCT recipients). However, CD45RA+ TCD DLI showed a trend toward improved 1-year COVID-19–free survival (p = 0.058) and significantly better survival among HSCT recipients (p = 0.0362). Viral clearance was achieved in most patients (90.9% vs. 83.3%). Immunomonitoring revealed distinct immune dynamics: between weeks 5–8, IFN-γ CCS VST promoted naïve T-cell expansion with broad cytokine elevation, while CD45RA+ TCD DLI expanded memory T cells with a more restricted cytokine profile. IFN-γ CCS VST also elicited stronger in vivo expansion of SARS-CoV-2–specific CD4 + and CD8 + T cells. In summary, both ATT approaches are safe and effective in immunocompromised patients with persistent COVID-19. CD45RA+ TCD DLI, which can be generated from convalescent donors as an off-the-shelf product, may provide a practical strategy for pandemic preparedness and treatment of vulnerable patients with immune senescence.

Open Access: Yes

DOI: 10.1007/s11357-025-02050-5

Tensor Product Alternatives for Nonlinear Field-Oriented Control of Induction Machines

Miklós Kuczmann Krisztian Horvath

Publication Name: Electronics Switzerland

Publication Date: 2024-04-01

Volume: 13

Issue: 7

Page Range: Unknown

Description:

The paper presents a nonlinear field-oriented control technique based on the tensor product representation of the nonlinear induction machine model and the solvability of linear matrix inequalities. The nonlinear model has 32 quasi linear parameter-varying equivalent variants, and it is shown that only half of the models result in feasible controller. Two control goals are realized: torque control and speed control. The controller is a nonlinear state feedback controller completed by integral action. A new block diagram is investigated for speed control. The controller gains are designed by the solution of linear matrix inequalities to solve the Lyapunov inequality to obtain a stable and fast response and constraints on the control signal. The presented methods are verified and compared by simulations.

Open Access: Yes

DOI: 10.3390/electronics13071405

Investigating the relationship between the theoretical layer thickness of the graphite lubricant film and the Kudo's friction number in the case of forged parts.

Tamás Ibriksz F. Tancsics

Publication Name: Iop Conference Series Materials Science and Engineering

Publication Date: 2018-10-18

Volume: 426

Issue: 1

Page Range: Unknown

Description:

In case of numerical analysis of forged parts, it is important to specify the friction coefficient characterizing the lubrication conditions. In our paper we present a combined method of a known SU (Simple Upsetting) deformation with EDS (Energy Dispersive Spectroscopy), which shows the relationship between the Kudo's friction number (this friction model is applicable for metalworking processes which produces high surface pressure) and the theoretical layer thickness of the graphite film covering the sink cavity. The tests were accomplished considering the solids content of non-synthetically produced lubricant concentrates diluted to varying degrees.

Open Access: Yes

DOI: 10.1088/1757-899X/426/1/012047

Logistic conception for real-time based info-communication system applied in selective waste gathering

I. Lakatos Ádám Titrik T. Péter

Publication Name: 2017 IEEE 14th International Scientific Conference on Informatics Informatics 2017 Proceedings

Publication Date: 2017-03-27

Volume: 2018-January

Issue: Unknown

Page Range: 203-209

Description:

Decreasing of available raw materials, fossil energy source and new approach made recycling necessary and inevitable. For recycling selective waste areas have been placed, where inhabitants can drop their waste for free. Waste containers have different saturation time, while gathering process is predefined, therefore independently whether it is needed or not they will be emptied. Further problem is that there is no optimization on the way to the container, which results in serious environmental load (noise and air pollution). This study deals with high level route optimization to minimize environmental load concerning noise and air pollution and by the application of real-time communication the appropriate containers are only going to be emptied.

Open Access: Yes

DOI: 10.1109/INFORMATICS.2017.8327247

Algorithm for D-V cells and fundamental domains, E4 space groups with broken translations in the icosahedral family

László Ács Emil Molnár

Publication Name: Journal for Geometry and Graphics

Publication Date: 2002-01-01

Volume: 6

Issue: 1

Page Range: 1-16

Description:

As a continuation of our earlier work [2] we extend our algorithm for E4-space groups in the icosahedral family, where non-lattice translations (broken translations) occur as well. So we obtain new 4-polytopes as fundamental domains from D-V cells of crystallographic orbits. We illustrate our situations by some characteristic examples. A computer program will produce further results.

Open Access: Yes

DOI: DOI not available