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This paper addresses the problem of designing secure control for networked multi-agent systems (MASs) under Denial-of-Service (DoS) attacks. We propose a constructive design method based on the interaction topology. The MAS with a non-attack communication topology, modeled by quasi-Abelian Cayley graphs subject to DoS attacks, can be represented as a switched system. Using switching theory, we provide easily implementable sufficient conditions for the networked MAS to remain asymptotically stable despite DoS attacks. Our results are applicable to both continuous-time and discrete-time systems, as well as to discrete-time systems with variable steps or systems that combine discrete and continuous times. [ABSTRACT FROM AUTHOR]

Introduction: Methamphetamine is a highly stimulating psychoactive drug that causes life-threatening addictions and affects millions of people around the world. Its effects on the brain are complex and include disturbances in the neurotransmitter systems and neurotoxicity. There are several known treatment methods, but their effectiveness is moderate. It must be emphasised that no drugs have been approved for treatment. For this reason, there is an urgent need to develop new, effective, and safe treatments for methamphetamine. One of the potential treatments is mindfulness meditation. In recent years, this technique has been researched extensively in the context of many neurological and psychiatric disorders. Methods: This review explores the use of mindfulness in the treatment of methamphetamine addiction. Searches were conducted in the PubMed/Medline, Research Gate, and Cochrane databases. Results: Ten studies were identified that used mindfulness-based interventions in the treatment of methamphetamine addiction. The results show that mindfulness is an effective form of reducing hunger, risk of relapses, stress indicators, depression, and aggression, alone or in combination with transcranial direct current stimulation (tDCS). Mindfulness also improved the cognitive function in addicts. The included studies used only behavioural measures. The potential mechanisms of mindfulness in addiction were explained, and it was proposed that it can induce neuroplasticity, alleviating the symptoms of addiction. Conclusions: Evidence from the studies suggest that mindfulness may be an effective treatment option for methamphetamine addiction, used alone or in combination with tDCS. However, further high-quality research is required to establish the role of this treatment option in this field. The use of neuroimaging and neurophysiological measures is fundamental to understand the mechanisms of mindfulness. [ABSTRACT FROM AUTHOR]

• This was a long-term (6 months) observational study of graft function in kidney transplant recipients after severe acute respiratory syndrome coronavirus 2 infection. • There were no significant changes in graft function before and after COVID-19 either the median level of creatinine (1.25 vs 1.26 mg/dL) or estimated glomerular filtration rate according to the Chronic Kidney Disease Epidemiology Collaboration equation formula results (61 vs 58 mL/min/1.73 m2). • Graft function remained stable during the COVID-19 infection even in the subpopulation of kidney transplant recipients with the highest comorbidity index (Charlson Comorbidity Index ≥ 3). • Graft function did not change in the most frail subpopulation, which scored greater than 3 on the Clinical Frailty Scale. Kidney transplant recipients (KTRs) are at an increased risk of infection with severe acute respiratory syndrome coronavirus 2, with mortality from 13% to over 30%. However, data concerning the influence of COVID-19 on long-term graft function in convalescents is lacking. The aim of this study was to evaluate the influence of COVID-19 on graft function at 6 months after recovery. A longitudinal controlled study was conducted in a group of 1058 KTRs. Of 180 patients with COVID-19 in the past, 77 KTRs (45 male) with a mean age 50.57 ± 13.37 years, Charlson Comorbidity Index of 3 (median; interquartile range [IQR], 3-5), Fragility Score of 3 (median; IQR, 3-3), and minimum 6 months after acute COVID-19 were included. The most common symptoms were weakness (75.33%), fever (74.03%), cough (51.95%), and loss of appetite (48.05%). Thirty-three patients were hospitalized; none required invasive ventilation therapy, but 16 required oxygen support. The treatment of COVID-19 included antibiotics (38.96%), thromboprophylaxis (25.97%), and nonsteroidal anti-inflammatory drugs, or paracetamol (25.97%). The median (IQR) values of serum creatinine 3 months before the onset and 6 months after COVID-19 were 1.25 (0.98-1.86) and 1.26 (1.03-1.78) mg/dL (nonsignificant difference); in strata analysis, there were also no differences with regards to patients with higher and lower comorbidity (3 < Charlson Comorbidity Index < 3) and fragility (3 < Fragility Score < 3). Furthermore, creatinine concentration in KTRs and controls did not differ. In the group of KTRs with a mild course of COVID-19, no negative impact of the infection on graft function was observed 6 months after transplantation. [ABSTRACT FROM AUTHOR]

Systems of fractional differential equations with a general form of fractional derivative are considered. A unique continuous solution is derived using the Banach fixed point theorem. Additionally, the dependence of the solution on the fractional order and on the initial conditions are studied. Then the stability of autonomous linear fractional differential systems with order 0<α<1 of the ψ‐Caputo derivative is investigated. Finally, an application of the theoretical results to the problem of the leader‐follower consensus for fractional multi‐agent systems is presented. Sufficient conditions are given to ensure that the tracking errors asymptotically converge to zero. The results of the paper are illustrated by some examples. [ABSTRACT FROM AUTHOR]

This work offers a real-world application for the study of fuzzy dynamic equations. First, we propose the novel concept of granular delta differentiability for fuzzy-valued functions defined on time scales with the help of the relative distance measure fuzzy arithmetic and horizontal membership functions. Then, fundamental foundations of fuzzy calculus on time scales are provided. Discussion on the Malthusian model defined on particular time scales to illustrate the proposed approach is presented. [ABSTRACT FROM AUTHOR]

In this paper, the study of multiobjective variational problems with time delay is introduced. We provide methods for identifying Pareto optimal solutions. We also prove necessary and sufficient optimality conditions for the isoperimetric problem with multiple constraints and delayed arguments. [ABSTRACT FROM AUTHOR]

Assessing the long-term stability of abandoned mine workings is a challenging problem in geo-mechanical engineering. There are several factors contributing to the long-term behaviour of excavations. Creep and the gradual deterioration of rocks are, in particular, among the dominant factors affecting the long-term stability of abandoned mine workings. In this paper, the mechanism of post-mining subsidence over old room-and-pillar mine workings is investigated. A case history of post-mining subsidence over Cow Pasture abandoned limestone mine in the West Midlands of the UK is presented. The geological and geotechnical characteristics of the mining site are explained. Empirical and analytical approaches are then used to study the mechanisms of post-mining subsidence. Outcomes of the analyses show that the bearing capacity failure of the roof strata and the gradual punching of pillars into the moisture-sensitive roof layers have been the key mechanisms initiating failure and leading to the formation of post-mining subsidence in the Cow Pasture Mine. [ABSTRACT FROM AUTHOR]

This paper deals with an opinion formation model, that obeys a nonlinear system of fractional-order differential equations. We introduce a virtual leader in order to attain a consensus. Sufficient conditions are established to ensure that the opinions of all agents globally asymptotically approach the opinion of the leader. We also address the problem of designing optimal control strategies for the leader so that the followers tend to consensus in the most efficient way. A variational integrator scheme is applied to solve the leader–follower optimal control problem. Finally, in order to verify the theoretical analysis, several particular examples are presented. [ABSTRACT FROM AUTHOR]

Abstract Anthropogenic activity related to the extraction of gas and oil, raw materials or water pumping leads to slow or rapid ground deformation. The ground motion rate is related to the type of the mined material, geological conditions, mining methods and other factors. Ground subsidence resulting from the collapse of underground post-mining voids occurs gradually. Mining-induced earthquakes and seismic earthquakes are largely unpredictable and have an adverse impact on the local inhabitants and buildings. For this reason, monitoring of this phenomenon is a challenge. The application of interferometric SAR for the evaluation of ground movement has brought satisfactory results over the past twenty years mainly in the regions where no other measurements were conducted during ground subsidence. In this paper we have examined a mining-induced earthquake with a magnitude 4.5 which occurred in an underground copper ore mine in Poland on 29th November 2016 and caused eight fatalities. It also had an impact on ground surface deformation in the vicinity of the mine tailings. An assessment of the earthquake-related impact on surface movement was carried out by Sentinel-1 TOPS time series interferometry. The velocity of ground movement and the scale of the phenomenon were investigated. In addition, the impact of the mining-induced earthquake on Zelazny Most mine tailings site was analyzed. Moreover, the process of dynamic ground compaction was also investigated in detail. Ground movement following the mine earthquake was explored. Two time phases of the movements were determined. The first phase of dynamic ground displacement was rapid and 90% of total ground deformation appeared on the surface within 7 days. The second phase of displacement was a 'vanishing' one; it lasted for approx. 3 weeks and 10% of ground deformation appeared on the surface. The study revealed that the maximum observed ground subsidence did not exceed 9 cm. The presented results contribute to a better understanding of post-earthquake ground deformations in the light of their spatial distribution in time. Highlights • Sentinel-1 interferometry is used to assess subsidence caused by mining-induced earthquake (M W 4.5). • About 92% of total subsidence occurred within 48 h after mining-induced earthquake. • Substantial ground movement stopped 7 days after the earthquake (M W 4.5). • Contribution to studies on ground movements which result from mining-induced earthquake. [ABSTRACT FROM AUTHOR]

This paper deals with control strategies for discrete-time fractional multi-agent systems. By using the discrete fractional order operator we introduce memory effects to the considered problem. Necessary optimality conditions for discrete-time fractional optimal control problems with single- and double-summator dynamics are proved, and simulation results are presented. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of the initial value problem of nonlinear fractional differential equations involving a Caputo-type fractional derivative with respect to another function. Existence and uniqueness results for the problem are established by means of the some standard fixed point theorems. Next, we develop the Picard iteration method for solving numerically the problem and obtain results on the long-term behavior of solutions. Finally, we analyze a population growth model and a gross domestic product model with governing equations being fractional differential equations that we have introduced in this work. [ABSTRACT FROM AUTHOR]

In this paper, a leader-following consensus of discrete-time multi-agent systems with nonlinear intrinsic dynamics is investigated. We propose and prove conditions ensuring a leader-following consensus. Numerical examples are given to illustrate our results. [ABSTRACT FROM AUTHOR]

The modeling of strains and deformations in salt mine areas encounters considerable difficulties because of the varying strength properties of salt, the complex morphological build of dome deposits and the rheological properties of salt. These properties have impacted the development of salt extraction for hundreds of years and the fact that the accurate determining of strains in a given specified moment and place are burdened with high uncertainty. Numerical modeling is useful when the model is reduced to one or several salt chambers. A broader range of underground post mining void considerably lowers the accuracy and efficiency of the calculations of such models. Stochastic models allow for a 3D modeling of the entire mining complex deposit, provided the model has been parametrized in detail. The methods of strains and deformations modeling were presented on the example of one of the biggest salt mines in Europe, where a volume of over 21 million m³ of salt was extracted. The stochastic model could be parametrized thanks to the documented results of measurements of convergence of the underground mining panels and leveling on the surface. The use of land subsidence inversion in the least squares method allowed for estimating the optimum values of parameters of the model. Ground deformation modeling was performed using the two-parameter time function, which allows for a simulation to be carried out in time. In the simulation, the convergence of underground excavations and the transition in time the effects of convergence into ground subsidence was taken into account. The detailed analysis of the geological conditions lead to modeling deviation of the subsidence trough. The accuracy of the modeling results was qualitatively and quantitatively confirmed by a comparison of the modeled to measured values of the vertical ground movement. The scaled model can be applied in future mining extraction projects in order to predict the strains and deformations for an arbitrary moment in time. [ABSTRACT FROM AUTHOR]

In this paper, we consider variational problems with delayed argument. Simple proofs of the first and second Noether theorems are given. Applying our results to some concrete problems we obtain conservation laws for systems with delay. [ABSTRACT FROM AUTHOR]

In this note we present a counterexample to Theorem 24 in G.S.F. Frederico and D.F.M. Torres (2010) [3] . [ABSTRACT FROM AUTHOR]

The time scale calculus theory can be applicable to any field in which dynamic processes are described by discrete- or continuous-time models. On the other hand, many economic models are dynamic models. Therefore it is natural to relate those two subjects. This work is intended to motivate the use of the calculus of variations and optimal control problems on time scales in the study of economic models. We show that a phenomenon known from the theory of behavioral economics may be described and analyzed by dynamical systems on time scales. [ABSTRACT FROM AUTHOR]

Weather extremes may have strong effects on biodiversity, as known from theoretical and modelling studies. Predicted negative effects of increased weather variation are found only for a few species, mostly plants and birds in empirical studies. Therefore, we investigated correlations between weather variability and patterns in occupancy, local colonisations and local extinctions (metapopulation metrics) across four groups of ectotherms: Odonata, Orthoptera, Lepidoptera, and Reptilia. We analysed data of 134 species on a 1×1 km-grid base, collected in the last 20 years from the Netherlands, combining standardised data and opportunistic data. We applied dynamic site-occupancy models and used the results as input for analyses of (i) trends in distribution patterns, (ii) the effect of temperature on colonisation and persistence probability, and (iii) the effect of years with extreme weather on all the three metapopulation metrics. All groups, except butterflies, showed more positive than negative trends in metapopulation metrics. We did not find evidence that the probability of colonisation or persistence increases with temperature nor that extreme weather events are reflected in higher extinction risks. We could not prove that weather extremes have visible and consistent negative effects on ectothermic species in temperate northern hemisphere. These findings do not confirm the general prediction that increased weather variability imperils biodiversity. We conclude that weather extremes might not be ecologically relevant for the majority of species. Populations might be buffered against weather variation (e.g. by habitat heterogeneity), or other factors might be masking the effects (e.g. availability and quality of habitat). Consequently, we postulate that weather extremes have less, or different, impact in real world metapopulations than theory and models suggest. [ABSTRACT FROM AUTHOR]

Introduction: Patients after SARS-CoV-2 infection frequently face "Post-COVID-19 Syndrome", defined by symptoms that develop during or after COVID-19, continue for more than 12 weeks, and are not explained by an alternative diagnosis. We aimed to evaluate the presence of post-COVID-19 syndrome and its predictors in kidney transplant recipients (KTR) 6 months after the disease. Materials and Methods: A total of 67 KTR (38 m) with a mean age of 53.6 ± 14 years, 7.3 ± 6.4 years post-transplant were included in the cohort longitudinal study. Thirty-nine (58.2%) of them were hospitalized, but not one required invasive ventilation therapy. They were interviewed 6 months after being infected, with a series of standardized questionnaires: a self-reported symptoms questionnaire, the modified British Medical Research Council (mMRC) dyspnea scale, EQ-5D-5L questionnaire, and EQ-VAS scale. Results: Post-COVID-19 syndrome was diagnosed in 70.1% of KTR and 26.9% of them reported at least three persistent symptoms. The most common symptoms were fatigue (43.3%), hair loss (31.3%), memory impairment (11.9%), muscle aches, and headaches (11.9%). Dyspnea with an mMRC scale grade of at least 1 was reported by 34.3% patients vs. 14.9% before infection; 47.8% stated that they still feel worse than before the disease. Mean EQ-VAS scores were 64.83 vs. 73.34 before infection. The persistent symptoms are more frequent in older patients and those with greater comorbidity. Conclusions: Persistent symptoms of post-COVID-19 syndrome are present in the majority of KTR, which highlights the need for long-term follow-up as well as diagnostic and rehabilitation programs. [ABSTRACT FROM AUTHOR]

We extend the second Noether theorem to fractional variational problems which are invariant under infinitesimal transformations that depend upon r arbitrary functions and their fractional derivatives in the sense of Caputo. Our main result is illustrated using the fractional Lagrangian density of the electromagnetic field. [ABSTRACT FROM PUBLISHER]

We prove optimality conditions for generalized quantum variational problems with a Lagrangian depending on the free end-points. Problems of calculus of variations of this type cannot be solved using the classical theory. [ABSTRACT FROM AUTHOR]

Defects in the core of SrLaGaO4 single crystals, grown by the Czochralski method using a [001]-oriented seed, were studied by transmission X-ray diffraction projection topography. Topographs were taken with radiation from a laboratory source and with high-energy radiation available at the ESRF beamline ID19 in Grenoble. The contrast of the investigated defect images was analysed for various diffraction vectors g and for various values of the product μ0 t (μ0 is the linear absorption coefficient and t the crystal thickness). This allowed the contrast formation to be studied as a function of absorption. The results of the analysis confirm the model of crystal lattice deformation around rod-like volume defects in SrLaGaO4 crystals. [ABSTRACT FROM AUTHOR]

We extend the second Noether theoremto variational problems on time scales. As corollarieswe obtain the classical second Noether theorem, the second Noether theorem for the h-calculus and the second Noether theorem for the q-calculus. [ABSTRACT FROM AUTHOR]

Abstract: We study operators that are generalizations of the classical Riemann–Liouville fractional integral, and of the Riemann–Liouville and Caputo fractional derivatives. A useful formula relating the generalized fractional derivatives is proved, as well as three relations of fractional integration by parts that change the parameter set of the given operator into its dual. Such results are explored in the context of dynamic optimization, by considering problems of the calculus of variations with general fractional operators. Necessary optimality conditions of Euler–Lagrange type and natural boundary conditions for unconstrained and constrained problems are investigated. Interesting results are obtained even in the particular case when the generalized operators are reduced to be the standard fractional derivatives in the sense of Riemann–Liouville or Caputo. As an application we provide a class of variational problems with an arbitrary kernel that give answer to the important coherence embedding problem. Illustrative optimization problems are considered. [Copyright &y& Elsevier]

Abstract: This paper presents the Euler–Lagrange equations for fractional variational problems with multiple integrals. The fractional Noether-type theorem for conservative and nonconservative generalized physical systems is proved. Our approach uses well-known notion of the Riemann–Liouville fractional derivative. [Copyright &y& Elsevier]

Abstract: We introduce differential, integral, and variational delta embeddings. We prove that the integral delta embedding of the Euler–Lagrange equations and the variational delta embedding coincide on an arbitrary time scale. In particular, a new coherent embedding for the discrete calculus of variations that is compatible with the least-action principle is obtained. [Copyright &y& Elsevier]

The calculus of variations on time scales is considered. We propose a new approach to the subject that consists of applying a differentiation tool called the contingent epiderivative. It is shown that the contingent epiderivative applied to the calculus of variations on time scales is very useful: it allows to unify the delta and nabla approaches previously considered in the literature. Generalized versions of the Euler–Lagrange necessary optimality conditions are obtained, both for the basic problem of the calculus of variations and isoperimetric problems. As particular cases one gets the recent delta and nabla results. [ABSTRACT FROM PUBLISHER]

Abstract: We give a proper fractional extension of the classical calculus of variations by considering variational functionals with a Lagrangian depending on a combined Caputo fractional derivative and the classical derivative. Euler–Lagrange equations to the basic and isoperimetric problems as well as transversality conditions are proved. [Copyright &y& Elsevier]

We study fractional variational problems in terms of a generalized fractional integral with Lagrangians depending on classical derivatives, generalized fractional integrals and derivatives. We obtain necessary optimality conditions for the basic and isoperimetric problems, as well as natural boundary conditions for free-boundary value problems. The fractional action-like variational approach (FALVA) is extended and some applications to physics discussed. [ABSTRACT FROM AUTHOR]

Abstract: The study of fractional variational problems in terms of a combined fractional Caputo derivative is introduced. Necessary optimality conditions of Euler–Lagrange type for the basic, isoperimetric, and Lagrange variational problems are proved, as well as transversality and sufficient optimality conditions. This allows to obtain necessary and sufficient Pareto optimality conditions for multiobjective fractional variational problems. [Copyright &y& Elsevier]

We present a unified treatment to control problems on an arbitrary time scale by introducing the study of forward-backward optimal control problems. Necessary optimality conditions for delta-nabla isoperimetric problems are proved, and previous results in the literature are obtained as particular cases. As an application of the results of the paper we give necessary and sufficient Pareto optimality conditions for delta-nabla bi-objective optimal control problems. [ABSTRACT FROM PUBLISHER]

In this work we study a quasilinear system of equations on time scales. Using the Krasnoselskii fixed-point theorem, sufficient conditions are given for the existence of positive solutions. [ABSTRACT FROM AUTHOR]

Abstract: We prove the Euler–Lagrange delta-differential equations for problems of the calculus of variations on arbitrary time scales with delta-integral functionals depending on higher-order delta derivatives. [ABSTRACT FROM AUTHOR]

Abstract: The fundamental problem of the calculus of variations on time scales concerns the minimization of a delta-integral over all trajectories satisfying given boundary conditions. This includes the discrete-time, the quantum, and the continuous/classical calculus of variations as particular cases. In this note we follow Leitmann’s direct method to give explicit solutions for some concrete optimal control problems on an arbitrary time scale. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the necessary and sufficient optimality conditions for problems of the fractional calculus of variations with a Lagrangian depending on the free end-points. The fractional derivatives are defined in the sense of Caputo. [Copyright &y& Elsevier]

We introduce a fractional theory of the calculus of variations for multiple integrals. Our approach uses the recent notions of Riemann–Liouville fractional derivatives and integrals in the sense of Jumarie. The main results provide fractional versions of the theorems of Green and Gauss, fractional Euler–Lagrange equations, and fractional natural boundary conditions. As an application we discuss the fractional equation of motion of a vibrating string. [ABSTRACT FROM AUTHOR]

We introduce the notion of strong local minimizer for the problems of the calculus of variations on time scales. Simple examples show that on a time scale a weak minimum is not necessarily a strong minimum. A time scale form of the Weierstrass necessary optimality condition is proved, which enables to include and generalize in the same result both continuous-time and discrete-time conditions [ABSTRACT FROM AUTHOR]

We address the problem of obtaining well-defined criteria for multiple criteria optimal control problems. Necessary and sufficient conditions for an objective functional to be nonessential are proved. The results provide effective tools for determining nonessential objectives in multiobjective optimal control problems. [ABSTRACT FROM AUTHOR]

The presented research aimed to evaluate the spatio-temporal distribution of ground movements caused by groundwater head changes induced by mining. The research was carried out in the area of one of the copper ore and anhydrite mines in Poland. To determine ground movements, classical surveying results and the persistent scatter Satellite Radar Interferometry (PSInSAR) method were applied. The mining operation triggered significant subsidence, reaching 1.4 m in the years 1944–2015. However, subsidence caused by groundwater pumping was about 0.3 m. After mine closure, an ongoing groundwater rebound was observed. Hence, land uplift occurred, reaching no more than 29 mm/y. The main part of the investigation concerned developing a novel method for uplift prediction. Therefore, an attempt was made to comparatively analyze the dynamics of ground movements correlated with the mine life and hydrogeological condition. These analyses allowed the time factor for the modeling of land uplift to be determined. The investigation also revealed that in the next six years, the uplift will reach up to 12 mm/y. The developed methodology could be applied in any post-mining area where groundwater-rebound-related uplift is observed. [ABSTRACT FROM AUTHOR]

Earthquake occurrence is usually unpredictable apart from sites in the vicinity of volcanoes. It is not easy to measure displacements caused by seismic phenomena using classical geodetic methods, which are based on point survey. Therefore, the surveying of ground movements caused by seismic events should be carried out continuously. Nowadays, remote sensing data and InSAR are often applied to monitor ground displacements in areas affected by seismicity. The effects of severe nearby mining-induced earthquakes have been discussed in the paper. The earthquakes occurred in 2017 and had a magnitude of 4.7 and 4.8. The distance between the epicenters of the mining-induced earthquakes was around 1.6 km. The aim of the investigation has been to analyze the spatio-temporal distribution of ground movements caused by the two tremors using the InSAR technique. Superposition of surface displacement has been studied in time and space. The main scientific aim has been to prove that in the areas where high-energy tremors occur, ground movements overlap. Due to proximity between the epicenters, the mining-induced earthquakes caused the formation of a large subsidence trough with the dimension of approximately 1.2 km × 4.2 km and total subsidence of ca. 116 mm. Two-time phases of subsidence were determined with temporal overlapping. The subsidence analysis has enhanced the cognition of the impact of mining-induced seismicity on the kinematics of surface changes. Moreover, the present work supports the thesis that InSAR is a valuable and adequately accurate technique to monitor ground displacements caused by mining induced earthquakes. [ABSTRACT FROM AUTHOR]

• Sinkholes pose significant hazards in populated areas. • We investigated early detection of sinkholes using Persistent Scatterer (PS) Interferometry. • Accelerating subsidence may indicate sinkhole occurence. Unexpectedly occurring sinkholes caused by shallow submerged voids are one of the key problems of intensively built-up post-mining areas. Five percent of Poland's territory is still under the influence of post-mining deformation. Impending sinkholes, which tend to develop randomly over very large areas, cannot be detected by using traditional geophysical methods. Moreover, geodetic measurement methods like Global Positioning System (GPS) analyses, tachymetry, laser scanning, or photogrammetry may be useful only for the registration of the dimensions and locations of sinkholes that have already occurred. Here, we investigate an area in Upper Silesia, Poland, where 345 sinkholes were recorded over a period of more than 20 years (1992–2013). Most of the events occurred in intensively built-up areas, and thus, these sinkholes posed a direct threat to the population. In the test area, 11 sinkholes were detected with a maximum depth of 16 m and maximum dimension of 25 m. The root cause of sinkhole formation was the collapse of post-mining shallow voids. We used satellite radar technology to detect and monitor ground movements potentially associated with the impending sinkholes. The findings showed that the application of Persistent Scatterer Interferometry can support the identification of zones where sinkholes will occur, given adequate spatio-temporal sampling. A stack of Envisat Synthetic Aperture Radar (SAR) images acquired between March 2003 and August 2010 was used in the analysis, and the results confirmed that precursory ground movements were detectable at an early stage of sinkhole development. The land subsidence rate observed prior to sinkhole collapse was not constant in time. Accelerated ground movements within 100 m of an observed sinkhole were detected. We conclude that satellite measurements may provide significant support in the early identification of areas prone to sinkhole occurrence. [ABSTRACT FROM AUTHOR]

Oxide Dispersion Strengthened (ODS) ferritic steels are promising materials for the nuclear power sector. This paper presents the results of a study on the sintering process using the Spark Plasma Sintering (SPS) technique, focusing on ODS ferritic steel powders with different contents (0.3 and 0.6 vol.%) of Y2O3. The novelty lies in the analysis of the effect of pre-annealing treatment on powders previously prepared by mechanical alloying on the microstructure, mechanical, and thermal properties of the sinters. Using the SPS method, it was possible to obtain well-densified sinters with a relative density above 98%. Pre-annealing the powders resulted in an increase in the relative density of the sinters and a slight increase in their thermal conductivity. The use of low electron energies during SEM analysis allowed for a fairly good visualization of the reinforcing oxides uniformly dispersed in the matrix. Analysis of the Mössbauer spectroscopy results revealed that pre-annealing induces local atomic rearrangements within the solid solution. In addition, there was an additional spectral component, indicating the formation of a Cr-based paramagnetic phase. The ODS material with a higher Y2O3 content showed increased Vickers hardness values, as well as increased Young's modulus and nanohardness, as determined by nanoindentation tests. [ABSTRACT FROM AUTHOR]

Transplantation of HLA and/or KIR mismatched allogeneic hematopoietic stem cells can lead NK cells to different states of activation/inhibition or education/resetting and change anti‐tumor immunosurveillance. In this study, we used molecular relapse monitoring to investigate a correlation between either missing ligand recognition or variation of the cognate iKIR‐HLA pairs with clinical outcomes in patients with hematological malignancies requiring allogeneic hematopoietic stem cell transplantation (allo‐HSCT). Patients (N = 418) with acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL), myelodysplastic syndrome (MDS), or lymphoma receiving T‐cell repleted graft from HLA‐matched or partly mismatched unrelated donors between 2012 and 2020 in our center were included in this study. Missing‐ligand recognition was assessed through the presence or absence of recipients' HLA ligand for a particular inhibitory KIR (iKIR) exhibited by the donor. Inhibitory KIR‐HLA pair number variation was defined by loss or gain of a new cognate pair of HLA‐KIR within the new HLA environment of the recipient, compared with the donor's one. Considering the results of our research, we drew the following conclusions: (i) loss of iKIR‐HLA cognate pair for C1, C2, and/or Bw4 groups led to significant deterioration of disease‐free survival (DFS), molecular relapse, overall survival (OS) and non‐relapse mortality (NRM) for patients undergoing allo‐HSCT in the standard phase of the disease. This phenomenon was not observed in patients who underwent transplantation in advanced hematological cancer. (ii) The missing ligand recognition had no impact if the proportion of HLA mismatches was not considered; however, adjustments of HLA mismatch level in the compared groups highlighted the adverse effect of the missing ligand constellation. (iii) The adverse effect of adjusted missing ligand suggests a predominance of lost NK cell education over lost NK cell inhibition in posttransplant recipients' new HLA environment. Our results suggested that donors with the loss of an iKIR‐HLA cognate pair after transplantation should be avoided, and donors who provided an additional iKIR‐HLA cognate pair should be preferred in the allo‐HSCT donor selection process. [ABSTRACT FROM AUTHOR]

Background: Among many possible variables that can be associated with gratitude, researchers list personality traits. Considering that these relationships are not always consistent, the first purpose of the present study was to verify how the Big Five factors connect to dispositional gratitude in a sample of Polish participants. The second purpose was to assess the unique contribution of personality traits on gratitude with multiple regression analyses. Moreover, because much remains to be learned about whether these associations are indirectly influenced by different personal or social variables, the third goal was to explore the role of emotional intelligence as a potential mediational mechanism implicated in the relationship between personality traits and gratitude. Participants, Methods and Data Collection: The sample consisted of 712 Polish respondents who were aged between 17 and 88. Most of them were women (64.3%). They answered questionnaires concerning their personality traits, emotional intelligence, and gratitude. The research was conducted using the paper-and-pencil method through convenience sampling. Results: The results showed that both gratitude and emotional intelligence correlated positively and significantly with extraversion, openness to experience, agreeableness, and conscientiousness. Gratitude and emotional intelligence correlated negatively and significantly with neuroticism. The personality predictor of gratitude with the highest and positive standardized regression value was agreeableness, followed by openness to experience and extraversion. Neuroticism had a negative impact on gratitude. Conscientiousness was the only statistically insignificant predictor in the tested multiple regression model. Moreover, emotional intelligence mediated the relationship between four dimensions of personality (extraversion, openness to experience, agreeableness, and conscientiousness) and gratitude and acted as a suppressor between neuroticism and gratitude. Conclusion: The current study broadens our comprehension of the interaction among personality traits, emotional intelligence, and a grateful disposition. Moreover, it imparts a noteworthy foundation not only for the mediatory role of emotional intelligence between four dimensions of personality and gratitude but also for its suppressor effect between neuroticism and being grateful. [ABSTRACT FROM AUTHOR]