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The concept of an electric vehicle developed nearly 200 years ago, with European and U.S. inventors at the forefront. However, as the electric vehicle was sought after, so too was [...]

The implementation of a new intermediate-Hamiltonian Fock-space coupled-cluster (IHFSCC) scheme for the (3,0) sector of the Fock space is reported. In this IHFSCC approach, the three-body contributions in the cluster operator S(3,0)corresponding to the (3,0) sector of the Fock space are considered, while S(1,0)and S(2,0)at the (1,0) and (2,0) level only include one- and two-body operators. By introducing a suitable partition of the wave operator, the intermediate Hamiltonian, which only depends on the two-body operator of S(1,0), is obtained. S(2,0)and S(3,0)are not required within this new IHFSCC scheme, and a large reference space can be possibly employed. The performance of this (3,0) IHFSCC method in calculating triple ionization potentials and excitation energies for atoms and cations with a ground p3configuration as well as adiabatic excitation energies for some molecules is investigated. The effect of the number of active virtual orbitals and three different types of orbitals, i.e., reference orbitals, restricted open-shell Hartree–Fock orbitals (ROHF) of the target systems, and canonicalized ROHF orbitals, on IHFSCC results, is also studied. Our calculations indicate that reasonable results can be achieved with this (3,0) IHFSCC method when a minimal reference space is employed. Further increasing the number of active orbitals does not necessarily improve the results. In addition, the IHFSCC results using canonicalized ROHF orbitals generally agree well with reference values, and they are not very sensitive to the number of active orbitals compared with results using the reference orbitals. The new (3,0) IHFSCC method can be applied to open-shell systems with three unpaired electrons with reasonable accuracy at a relatively low computational cost.

The intimate mechanism of N2O decomposition on bare and redox-tuned Co3O4nanocubes (achieved by single (Li or K) and double (Li and K) doping) was elucidated. The catalysts synthesized by the hydrothermal method were characterized by X-ray electron absorption fine structure measurements, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and Kelvin Probe techniques. TPSR and steady-state isothermal catalytic tests reveal that the N2O turnover frequencies are critically sensitive to the work function of the catalysts, adjusted purposely by doping. For the catalysts obtained by one-pot hydrothermal synthesis, lithiation of the Co3O4nanocubes leads to the formation of {Li’8a, Co·16d} species, decreasing steadily the work function and the activity, while for the catalysts prepared by postsynthesis impregnation, formation of {Li’8a, Co’16d,Co··16c} species leads to a volcano-type dependence of the catalytic activity and the work function in parallel. The beneficial effect of potassium was discussed in terms of mitigation of surface potential buildup due to the accumulation of ionosorbed oxygen intermediates (surface electrostatics), which hinders the interfacial electron transfer. Analysis of the catalytic activity response to the redox tuning of Co3O4, substantiated by DFT calculations, allowed for a straightforward conceptualization of the redox nature of the N2O decomposition in terms of the lineup of frontier orbitals of the N2O/N2O–and O2–/O2reactants with the surface DOS structure and the resultant molecular orbital interactions. The positions of the virtual bonding 3πg0(N2O)−α-3dz2and the occupied 2πg1(O2–)−α-3dz2states relative to the Fermi energy level play a crucial role in the regulation of the forward and backward interfacial electron transfer events, which drive the redox process.

The paper presents the results of contact strength and tribological property tests of spare parts made of a popular resin using a 3D DLP printing technology. Two printer models by the same manufacturer were used in the study. The post-processing technique, which shapes the final functional properties, was diversified. Surface performance properties were compared, i.e. Shore hardness, indentation hardness, Martens hardness, elastic modulus, and parameters related to surface creep and relaxation. Tribo-logical durability in rotary motion and tribological wear in reciprocating linear motion were also evaluated using micro- and nanotribometers. This was followed by surface analyses of the friction track of the analysed materials using microscopic methods: a scanning electron microscope, a WLI interferometric microscope, and an optical microscope. The results were statistically processed and the relationship between the parameters determined in the indentation test was determined.

Until 2013, the substantive rules of Hungarian company law were regulated by various company acts. When Hungary adopted a new Civil Code in 2013, it included, for the first time in Hungarian legal history, the substantive rules of company law. One of the most controversial novelties of the new company law rules was the provision that gave unprecedented freedom to company members to deviate from the company law rules of the Civil Code, as long as the Civil Code does not expressly prohibit the deviation or it does not manifestly prejudice to the rights of creditors, employees or a minority of the members of the legal person or hider the supervision of the lawful operation of the legal person. This article analyses this provision from a comparative perspective. The analysis compares the English, American, German and Hungarian solutions and finds that there are significant differences regarding the right of the parties to determine the company’s articles of association. Building on the findings of this comparison, the article argues that a more enabling regulatory approach could facilitate the pursuit of interests beyond the narrow interests of company members, using the example of corporate purpose and employee participation.

Non-coding RNA (ncRNA) therapeutics can target either ncRNAs or conventional messenger RNA, offering both superior pharmacokinetics and selectivity to conventional therapies and addressing new, previously unexplored pathways. Although no ncRNA has yet been approved for the treatment of heart failure, in this review we present five most promising pathways and agents that either are in human clinical trials or offer great promise in the near future.

Barium–cobaltate-based perovskite (BaCoO3−δ) and barium–cobaltate-based nanocomposites have been intensively studied in energy storage and conversion devices mainly due to flexible oxygen stoichiometry and tunable nonprecious transition metal oxidation states. Although a rich and complex family of structural polymorphs has already been reported for these perovskites in the literature, the potential structural evolution that may occur during the oxygen reduction reaction and the oxygen evolution reaction has not been investigated so far. In this study, we synthesized and characterized the lowest Co-oxidation state possible in the compound, BaCoO2, which exhibits a quartz-derived, trigonal structure with a helicoidally corner-sharing, CoO4-tetrahedral-framework as already proposed by Spitsbergen et al. Oxygen can reversibly be inserted in such a crystal structure to form BaCoO3−δ, i.e., with 0 ≤ δ ≤ 1, based on the results of an in situcoupled thermogravimetric - neutron diffraction study and which presents therefore giant oxygen capacity storage due to the extreme tunability of the electronic configuration of the cobalt cations which defines the fundamental origins of the materials performance. The reversible conversion of BaCoO2to BaCoO3−δassociated with a similar electronic conductivity above 900 K permits to clarify the high potential of BaCoO3−δ-based energy storage and conversion devices.

3XMM J185246.6+003317 is a transient magnetar located in the vicinity of the supernova remnant Kes79. So far, observations have only set upper limits to its surface magnetic field and spindown, and there is no estimate for its mass and radius. Using ray-tracing modelling and Bayesian inference for the analysis of several light curves spanning a period of around three weeks, we have found that it may be one of the most massive neutron stars to date. In addition, our analysis suggests a multipolar magnetic field structure with a subcritical field strength and a carbon atmosphere composition. Due to the time-resolution limitation of the available light curves, we estimate the surface magnetic field and the mass to be log10⁡(B/G)=11.89−0.93+0.19and M=2.09−0.09+0.16M⊙at 1σconfidence level, while the radius is estimated to be R=12.02−1.42+1.44km at 2σconfidence level. They were verified by simulations, i.e., data injections with known model parameters, and their subsequent recovery. The best-fitting model has three small hot spots, two of them in the southern hemisphere. These are, however, just first estimates and conclusions, based on a simple ray-tracing model with anisotropic emission; we also estimate the impact of modelling on the parameter uncertainties and the relevant phenomena on which to focus in more precise analyses. We interpret the above best-fitting results as due to accretion of supernova layers/interstellar medium onto 3XMM J185246.6+003317 leading to burying and a subsequent re-emergence of the magnetic field, and a carbon atmosphere being formed possibly due to hydrogen/helium diffusive nuclear burning. Finally, we briefly discuss some consequences of our findings for superdense matter constraints.

Graphical Abstract:

The long COVID (coronavirus disease), a multisystemic condition following severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, is one of the widespread problems. Some of its symptoms affect the nervous system and resemble symptoms of Alzheimer’s disease (AD)—a neurodegenerative condition caused by the accumulation of amyloid beta and hyperphosphorylation of tau proteins. Multiple studies have found dependence between these two conditions. Patients with Alzheimer’s disease have a greater risk of SARS-CoV-2 infection due to increased levels of angiotensin-converting enzyme 2 (ACE2), and the infection itself promotes amyloid beta generation which enhances the risk of AD. Also, the molecular pathways are alike—misregulations in folate-mediated one-carbon metabolism, a deficit of Cq10, and disease-associated microglia. Medical imaging in both of these diseases shows a decrease in the volume of gray matter, global brain size reduction, and hypometabolism in the parahippocampal gyrus, thalamus, and cingulate cortex. In some studies, a similar approach to applied medication can be seen, including the use of amino adamantanes and phenolic compounds of rosemary. The significance of these connections and their possible application in medical practice still needs further study but there is a possibility that they will help to better understand long COVID.

The purpose of this work was to carry out comparative studies of WC-Co-Cr coatings deposited using the high velocity oxy fuel (HVOF) method onto two types of substrate material: structural steel S235 and magnesium alloy AZ31. The influence of the substrate material type on the microstructure, phase composition, crystallite size, porosity, Vickers microhardness, instrumental hardness (HIT), Young’s modulus (EIT), and fracture toughness was investigated. For both substrates, the deposited coatings deposited were characterized with fine-grained and compact microstructure. The X-ray diffraction (XRD) revealed presence of following phases: WC, W2C, Co0.9W0.1, and Co3W9C4. The WC phase was the most desirable and stable one with crystallites were below 100 nm. On the other hand, the size of the W2C crystallites was below 30 nm. The coatings obtained showed porosity values equal to 2.3 ± 0.4 vol% and 2.8 ± 0.7 vol% for AZ31 and S235, respectively. The average Vickers microhardness for both types of sample was appproximately 1200 HV0.3. The average HITvalues for carbide particles and metallic matrix were around 29 GPa and 6.5 GPa, respectively. In the case of EIT, it was around 620 GPa and 190 GPa for WC and Co-Cr, respectively. The differences between coatings were negligible. The EITvalue for both coatings was equal to 344 ± 11 GPa. The fracture toughness was around 4.5 MPa · m1/2in both cases. The investigations revealed that it is possible to replace steel substrate material with a much lighter equivalent, in this case AZ31 alloy, without deterioration of the coating properties.

A set of 6368 U–Pb isotope ages of detrital zircons from 53 samples of the Oligocene to Early Miocene Menilite and Krosno formations (Outer Western Carpathians) was obtained and interpreted in terms of their sources. In both units the most frequent are mid-Variscan and Cadomian zircons that were derived from the Variscan Internides underlying the studied basin, and from the Brunovistulia Terrane, respectively. The coincidence of detrital zircon ages and clast ages indicates that zircons of that age can be at least partly of first cycle. Sveconorwegian and Calymmian–Statherian recycled zircons of Baltica origin, highly frequent in the Menilite Formation, are most probably sourced from Lower Devonian sediments of the Małopolska Massif. The Oligocene basin of the Menilite Formation was supplied in detrital material largely from the north where the Meta-Carpathian Swell was elevated in the area of the Małopolska Massif and Brunovistulia Terrane. During sedimentation of the Krosno Formation this source expired. A considerable input to the Menilite Formation of Baltica derived zircons and a limited number of zircons from sources located SE of the study area suggests that they were deposited in a relatively shallow and isolated basin. Supplementary material: A list of samples collected, lithological features of sampled rocks and lithostratigraphic sub-units, methods of zircon separation and U–Pb dating, and detailed results of the dating of detrital zircons, with concordia plots and probability density diagrams are available at https://doi.org/10.6084/m9.figshare.c.7100071 [ABSTRACT FROM AUTHOR]

The research presents the results of an innovative metal forming technology: ‘axially asymmetric metal spinning’. Special attention was paid to the influence of two forming conditions: Constant Contact (CC)and Tangential Contact (TC). The influence of Constant Contact and Tangential Contact were examined and compared. The term Constant Contact was used to describe a forming zone fixed at a certain height. This attribute was defined as naturally occurring in axially symmetrical metal spinning. The term Tangential Contact was used as the opposite to Constant Contact. Tangential Contact was used to describe the phenomena of movement of the forming zone. This attribute was defined as naturally occurring in axially asymmetric metal spinning. For the purpose of comparison, an asymmetric mandrel was manufactured, for which two trajectories were engineered. The trajectories were designed with the CCand TCconditions. The Finite Element Method was used to conduct metal forming simulation in simufact.forming software. Experimental trials were performed on the spinning machine MWS—200. Aluminium Alloy 1050 A was used in the FEM and experimental tests. The geometry measurement was performed using an ATOS 3D scanner and GOM Inspect software. The measurement of residual stresses was performed on a Proto iXRD® diffractometer. After determining the specific requirements of the innovative axially asymmetric spinning technology, a special computer program, called RoMeFo, was created. RoMeFo’spurpose was to engineer the trajectory with the TCcondition for the mandrel’s full height. Depending on the method used, details with the following heights were manufactured in the experimental trials: CC—22mm, TC—30mm and RoMeFo—60mm.

Obesity is a disease which is currently one of the most serious problems affecting approximately 650 million people worldwide. Improper lifestyle is considered the primary cause of the disease; however, many other factors contribute to the problem. In recent years, attention has been drawn to the role of gut microbiota in developing and controlling obesity and overweight. Microorganisms in the gastrointestinal tract are responsible for the fermentation of certain nutrients, causing efficient digestion, stimulation of intestinal transit, vitamin production, and modulation of the host’s immune system. Numerous studies have demonstrated that gut microbiota composition differs between obese individuals and those with a normal body mass index (BMI). It has also been shown that altering gut microbiota can influence the phenotype of the host organism, promoting metabolic changes, including BMI reduction. Recent studies aimed at using probiotics to modify gut microbiota composition to reduce body weight are still inconclusive.

Socio-cognitive computing is a paradigm developed for the last several years in our research group. It consists of introducing mechanisms inspired by inter-individual learning and cognition into metaheuristics. Different versions of the paradigm have been successfully applied in hybridizing Ant Colony Optimization (ACO), Particle Swarm Optimization (PSO), Genetic Algorithms, Differential Evolution, and Evolutionary Multi-agent System (EMAS) metaheuristics. In this paper, we have followed our previous experiences in order to propose a novel mutation based on socio-cognitive mechanism and test it based on Evolution Strategy (ES). The newly constructed versions were applied to popular benchmarks and compared with their reference versions.

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and is the most common cause of dementia. The pathogenesis of AD still remains unclear, including two main hypotheses: amyloid cascade and tau hyperphosphorylation. The hallmark neuropathological changes of AD are extracellular deposits of amyloid-β (Aβ) plaques and intracellular neurofibrillary tangles (NFTs). Endocytosis plays an important role in a number of cellular processes including communication with the extracellular environment, nutrient uptake, and signaling by the cell surface receptors. Based on the results of genetic and biochemical studies, there is a link between neuronal endosomal function and AD pathology. Taking this into account, we can state that in the results of previous research, endolysosomal abnormality is an important cause of neuronal lesions in the brain. Endocytosis is a central pathway involved in the regulation of the degradation of amyloidogenic components. The results of the studies suggest that a correlation between alteration in the endocytosis process and associated protein expression progresses AD. In this article, we discuss the current knowledge about endosomal abnormalities in AD.

In this article, the local consensus problem of nonlinear time-delay multiagent systems with switching topologies via distributed saturated impulsive control is discussed and the maximum domain of attraction is well estimated. Specifically, we develop a new estimation approach that is quite distinct from the contractive invariant set to estimate the domain of attraction. Moreover, a novel composite impulsive-instant-dependent Lyapunov function is constructed and an improved convex hull representation with more slack variables is adopted to minimize the conservativeness. Then, some delay-independent sufficient criteria in the form of bilinear matrix inequalities that guarantee local consensus of nonlinear time-delay multiagent systems are obtained by means of the Lyapunov–Razumikhin technique and proof by contradiction. Through appropriate transformation, some linear matrix inequalities-based optimization problems constrained by the proposed local consensus criteria are formulated, and the corresponding numerical solutions are solved by the Yalmip. Finally, a simulation example is given to confirm the validity and superiority of the proposed theoretical results.

Watercourses serve the needs of agriculture in certain sections and are subject to strong anthropopressure. When agriculture prevails in the catchment, it often has abundant vegetation, macrophytes in particular, and the bottom is covered by a substantial layer of silt. In order to ensure patency of flow and access to water, small watercourses are very often subject to river maintenance works. The aim of the study was to assess the impact of 3 types of works on the diversity of fish species and density of fish in the 1 and 2 year after the works at 21 sites located on 8 rivers in the European Central Plains Ecoregion. As a result of the works, especially in the 1 year after the works, significant changes were found in hydrochemical and hydrological parameters, especially with the increase in velocity and mean depth in watercourses. Additionally, habitat change contributed to differences in the composition of the ichthyofaunal. After 1 year, the diversity of fish species and fish population density increased or remained unchanged after dredging and removal of plants from the river channel, but they decreased after the removal of macrophytes from river banks. After year 2, a decrease in the diversity of fish species and density was observed, associated with re-infestation and siltation of the watercourses. Particularly in the case of dredging and removal of macrophytes from the river bank, maintenance works should not be done too frequently, because some species of natural value disappear.

In this study we re-examined the postulate that in the rat age-related body metabolism and kidney function changes progress only slowly. Thus we checked whether a moderate between-animal age distance may cause any marked difference, which could affect interpretation of experimental results. Food and water consumption, renal sodium and potassium excretion and haemodynamics were lower in rats aged 15 versus 9 weeks. In turn, hematocrit, mean arterial pressure, and renal vascular resistance were significantly higher in older animals, whereas renal excretion of NO3-/NO2- and vascular endothelial growth factor A and in situ renal tissue NO signal did not differ. Evidently, an age older by 6 weeks was associated with decreased hydration, tone of systemic and renal blood vessels, and renal excretion. In conclusion, since the actual age is an important determinant of the animal’s functional status, accurate age-matching of experimental groups is a necessary pre-condition for correct data interpretation.

The Northern European Enclosure Dam (NEED) is a hypothetical project to prevent flooding in European countries following the rising ocean level due to melting arctic glaciers. This project involves the construction of two large dams between Scotland and Norway, as well as England and France. The anticipated cost of this project is 250 to 500 billion euros. In this paper, we present the simulation of the aftermath of flooding on the European coastline caused by a catastrophic break of this hypothetical dam. From our simulation results, we can observe a traveling wave after the accident, with a velocity of approximately 45 kms per hour, raising the sea level permanently inside the dammed region. This observation implies a need to construct additional dams or barriers protecting the Netherlands’ northern coastline and the Baltic Sea’s interior. Our simulations have been obtained using the following building blocks. First, a graph transformation model was applied to generate an adaptive mesh, refined towards the seabed and the seashore topography, approximating the topography of the Earth. We employ the composition graph grammar model to break the mesh’s triangular elements without generating hanging nodes. Second, the wave equation is formulated in a spherical latitude-longitude system of coordinates and solved by a high-order time integration scheme using the generalized αmethod. While our paper mainly focuses on the simulation of the NEED dam break, we also provide a stand-alone tool to generate an adaptive mesh of the whole Earth. We can use our software as a stand-alone package in FEniCS or other simulation software.

In this article, we investigate the leader–follower consensus of multiagent systems over finite fields, which model agents with limited capacities for storing, processing, and transmitting the information, from the perspectives of the transition graph and the characteristic polynomial of the network matrix, respectively. By the features of dynamics over finite fields, we reveal that the transition graph of networks achieving the leader–follower consensus over finite fields is either a spanning in-tree topped at zero-state or is composed of spanning in-trees with the same structure, topped at steady states. To address the high time complexity associated with transition graphs and existing methods, we integrate the characteristic polynomial of the network matrix with the cycle and tree structures in the transition graph. As a result, a concise criterion is established only based on the characteristic polynomial, which merely requires polynomial computational complexity with respect to the number of network nodes. Finally, a numerical example is presented to validate the effectiveness of the obtained theoretical results.

This article aims to consider the finite-time synchronization of a class of discontinuous fuzzy competitive networks with nondifferential leakage delays. Different from the previous competitive networks and leakage-delayed networks, the activation functions are discontinuous and the leakage delays are nondifferential. Without using the Lyapunov function methods, the synchronization in a finite time is investigated based on the comparison principle and inequality techniques, which are used for the first time in the study of the competitive networks and leakage-delayed networks. Moreover, the feedback controller and bounded feedback controller are designed to help achieve the finite-time synchronization. The bounded feedback controller is formulated by the function $\arctan$ and a new inequality lemma is given, which plays a vital role in achieving the synchronization via bounded feedback controller. Although both controllers can help achieve the finite-time synchronization, it can be found that there is a big difference that the value of feedback controller is greatly influenced by system's state variables, but bounded controller is not. Such fact leads to different settling-times. The conclusion is that bounded controller has more advantages in shortening convergence time through numerical simulations.

In this brief, we consider the stability of inertial memristor-based neural networks with time-varying delays. First, delayed inertial memristor-based neural networks are modeled as continuous systems in the flux-current-voltage-time domain via the mathematical model of Hewlett-Packard (HP) memristor. Then, they are reduced to delayed inertial neural networks with interval parameters uncertainties. Quasi-equilibrium points and quasi-stability are proposed. Quasi-stability criteria of delayed inertial memristor-based neural networks are obtained by matrix measure method, the Halanay inequality, and uncertainty technologies. In the end, a numerical example is provided to show the validity of our results.

The paper presents the results of research on the problem of the influence of various types of unmalted grain and its quantitative share on important parameters of the malt extract. The aim of the work was to control what precentage of unmalted grain can be added to malt, so that their starch is saccharified only thanks to the action of endogenous malt enzymes. The grains of millet, oats, buckwheat and spelt were used as unmalted raw materials. The basis of the mixture subjected to extraction was Pilsner type barley malt. The percentages of the additives ranged from 5 to 50%. Both the unmalted grain and the malt were crushed. The extract was prepared with the use of two methods: congress and infusion. Saccharification time, pH and extract content were tested. The results were analyzed statistically. It was found that the amount and type of unmalted raw material influenced the saccharification time of starch and the content of the extract and had no effect on the pH of the extract. Millet grain starch was saccharified if its amount was about 40% of the tested mixtures. In other variants of the experiment, endogenous malt enzymes were able to break down the starch when the amount of additive was as high as 50%.

Background: This paper presents the experimental and numerical studies of last-stage low-pressure (LP) mistuned steam turbine bladed discs during run-down. Methods: The natural frequencies and mode shapes of the turbine bladed disc were calculated using an FE model. The influence of the shaft on the modal properties, such as natural frequencies and mode shapes, was considered. The tip-timing method was used to find the mistuned bladed disc modes and frequencies. Conclusions: The experimental results from the tip-timing analysis show that the mistuning in combination with shaft coupling suppresses pure nodal diameter type blade vibrations associated with the fundamental mode shape of a cantilevered blade. Vibration modes emerge when even a single blade is vibrating due to the well-known mode localization caused by mistuning. The numerical results confirm this.

Data deduplication is of vital importance for mobile cloud computing to cope with the explosive growth of outsourced mobile data. In order to ensure the privacy of sensitive mobile data against an untrusted cloud, Message-Locked Encryption (MLE) has been proposed to enable deduplication over ciphertext. However, MLE prohibits data access control since it uses deterministic content-derived encryption keys. Recently, a lightweight rekeying-aware encrypted deduplication system (REED) has been proposed to achieve dynamic access control for secure data deduplication. However, REED is vulnerable to key-retaining attack and stub-retaining attack, which leads to insecure access revocation, and thus cannot support secure dynamic access control. In response, we present AC-Dedup, an encrypted deduplication storage system that supports secure dynamic access control for mobile cloud storage. At the core of AC-Dedup are two novel encryption techniques named mixed message locked encryption and random stub re-encryption to resist the two types of attacks, respectively. To the best of our knowledge, AC-Dedup is the first practical system that achieves secure data deduplication and secure dynamic access control simultaneously. We conduct security analysis and experimental evaluation on mobile device and cloud platform with real-world IoT datasets. The results show that AC-Dedup enables secure and efficient dynamic access control while preserving deduplication effectiveness.

Working capital management (WCM) concerns decisions on the levels and turnover of the inventories, receivables, cash and current liabilities of a company. Consequently, WCM affects the profitability of an enterprise. This paper aims to determine the relationship between profitability and WCM, characterised by components of the company’s operating cycle. The research is based on meta-analysis and meta-regression methods that allow for the combination and analysis of the outcomes of individual empirical studies using statistical methods. Our final research sample consists of 43 scientific papers from 2003 to 2018. These studies covered almost 62,000 enterprises in 35 countries from 1992 to 2017. Our results indicate that there is a common, negative relationship between profitability and the cash conversion cycle (CCC). This relationship is conspicuous in various countries and in different economic contexts. A negative, statistically significant relationship was also detected between profitability and average collection period (ACP), the accounts payable period (APP) and inventory turnover cycle (ITC) as well. We also identified moderators of the diagnosed dependencies on the grounds of macroeconomic and institutional factors. The richer the economy, the weaker a negative impact of CCC on profitability. The higher the protection of creditors and debtors, the weaker the negative relationship between profitability and ITC. The opposite is applicable to inflation and ACP and APP, unemployment and CCC, ACP and APP, the availability of credit and APP and the degree of capital market development and CCC and ACP. The aforementioned macroeconomic and institutional factors cause the negative relationship between particular components of the operating cycle and profitability to deepen even further. Our research contributes to the existing knowledge by confirming that the negative relationship between profitability and all components of the operating cycle is dominant in the global economy. It also indicates that there are macroeconomic and institutional moderators of the strength and direction of these relationships.

The dynamical system with a second-order + first-order structure has been proven to be effective for solving convex optimization problems with equality constraints. In this brief, this structure is extended to distributed optimization to deal with set-constrained convex optimization problems under strongly connected and weight-balanced directed topology, and a continuous optimization dynamics based on projection operator and primal-dual method is proposed. When proper values of the system parameters are selected, the dynamics converges quickly to the optimal solution of the problem. Finally, two numerical experiments are given to verify the effectiveness of the proposed model.

This work proposes a fully distributed moving horizon estimation method with an event-triggered communication strategy over wireless sensor networks. The proposed method calculates a local state estimation of each sensor by minimizing a quadratic objective function, which involves a fused arrival cost that is computed in a distributed manner. This approach adjusts data transmission rate by selectively transmitting local information and allows the incorporation of constraints on the noise and state variables. In addition, the estimation error is proved to be uniformly bounded in the mean square sense under the condition that the network topology is strongly connected and the system is collectively observable. Finally, a target tracking example is presented to demonstrate the validity of the proposed approach.

Both hydrogen peroxide and silver can oxidize organic and inorganic molecules, and this causes them to affect the metabolism of living organisms in many ways. The paper presents examples of the impact of H2O2and silver on stimulating plant growth and development and increasing plants’ resistance to biotic and abiotic stresses. The most underlined proposal for application in horticulture is the control of microorganisms during cultivating and storing vegetables, fruits, and flowers, aiming to replace synthetic pesticides. Preparations containing H2O2, silver, or both components can be widely used in horticulture for plant protection, in the form of spraying and soaking seedlings, to protect them during the time of storage, for disinfecting tubers, bulbs, and rhizomes before planting, for fogging potatoes and root vegetables during storage, for quick healing of wounds on the roots and aboveground parts of plants, after cutting and in the case of frost damage and injuries caused by winds, for disinfecting seeds, and, as stimulants of plant development and inducers of resistance to biotic and abiotic stresses. However, their practical use depends on obtaining the legislator’s consent for their broader use in horticultural production.

We reported a novel hydrated solid-state proton conductor’s structure, charge transport, and spectroscopic properties. The resulting material of the hydrated imidazolium (ImiHem·H2O) and pyrazolium (PyrHem·H2O) hemimelitate is a solid-state hydrate with one water molecule per structural unit. The ions in the crystal structure are connected by N+–H···O–hydrogen bonds and the anions are connected to the water molecules by O–H···O hydrogen bonds. The strength of the intermolecular hydrogen bonds is important for the thermal and conductive properties of the studied hemimelitic acid salts. The chain motif of the N+–H···O–hydrogen bonds influences the greater thermal stability of the salt. The weaker strength of the O–H···O hydrogen bonds leads to better conductive properties of the salt.

In this article, observable stochastic graphs and detetectable stochastic graphs are, respectively, defined with the detailed implementation for the observability and detectability of stochastic discrete-time and discrete-state dynamic systems. More specifically, they are generally two classes of vertex-colored and edge-labeled graphs rendering a walking agent therein to determine his initial and current positions, respectively, in probability one by measuring the color sequence of his traversed vertices. In the part of analysis, we follow the aforementioned two definitions and establish the corresponding polynomial-time verifying algorithms. Notably, the implicit formulas are also established to calculate the observability and detectability probability for any pairwise vertex pair. In the synthesis part, the minimal number of colors dyeing the vertices to make the considered graph stochastically observable and detectable is investigated, respectively. Our results indicate that the minimal coloring problem is NP-hard for observability in the stochastic situations but is solvable in polynomial time for detectability in the deterministic cases. The observability and detectability of stochastic finite-valued systems, assembling with the finite-cardinal state spaces, are validated as a compelling application of these two types of directed graphs, whereas the minimal sensors placement problems subject to observability and detectability problems are accordingly interpreted by the minimum set cover algorithm.

This article focuses on the fuzzy $\mathcal {H}_{\infty }$ control problem for a class of semi-Markov jump singularly perturbed nonlinear systems with actuator saturation. Nonlinearities in the underlying systems are tackled with the Takagi–Sugeno fuzzy model. As distinct from the previous achievements, the case that the semi-Markov kernel with partially known information is taken into account such that the underlying systems can be extended to a wider scope. Given that actuator saturation is ubiquitous in engineering systems, the convex hull method is embraced to address this circumstance. To reduce the conservativeness of the obtained results, on the basis of Lyapunov stability theory and LaSalle's invariance principle, some criteria related to the sojourn time are presented. Next, the mean-square exponential stability of the underlying system is obtained based on the derived results. Finally, further experiment to verify the feasibility of the proposed methodology is given by a tunnel diode circuit model.

This article studies the asynchronous fault detection filter problem for discrete-time memristive neural networks with a stochastic communication protocol (SCP) and denial-of-service attacks. Aiming at alleviating the occurrence of network-induced phenomena, a dwell-time-based SCP is scheduled to coordinate the packet transmission between sensors and filter, whose deterministic switching signal arranges the proper feedback switching information among the homogeneous Markov processes (HMPs) for different scenarios. A variable obeying the Bernoulli distribution is proposed to characterize the randomly occurring denial-of-service attacks, in which the attack rate is uncertain. More specifically, both dwell-time-based SCP and denial-of-service attacks are modeled by means of compensation strategy. In light of the mode mismatches between data transmission and filter, a hidden Markov model (HMM) is adopted to describe the asynchronous fault detection filter. Consequently, sufficient conditions of stochastic stability of memristive neural networks are devised with the assistance of Lyapunov theory. In the end, a numerical example is applied to show the effectiveness of the theoretical method.

This paper is concerned with a Nash equilibrium (NE) tracking issue in online games with bandit feedback, where cost functions vary with time and agents only have access to the values of these functions at two points during each round. A partial-decision information setting is considered, in which agents have only access to the decisions of their neighbors. The primary objective of this paper is to develop a distributed online NE tracking algorithm that ensures sublinear growth of regret with respect to the total round T, under both the bandit feedback and partial-decision information setting. By utilizing a two-point estimator together with the leader-following consensus method, a new distributed online NE tracking algorithm is established with the estimated gradient and local estimated decisions based on the projection gradient-descent method. Moreover, sufficient conditions are derived to guarantee an improved upper bound of dynamic regret compared to existing bandit algorithms. Finally, a simulation example is presented to demonstrate the effectiveness of the proposed algorithm.

In this article, a novel hybrid reinforcement $Q$ -learning control method is proposed to solve the adaptive fuzzy $H_{\infty }$ control problem of discrete-time nonlinear Markov jump systems based on the Takagi–Sugeno fuzzy model. First, the core problem of adaptive fuzzy $H_{\infty }$ control is converted to solving fuzzy game coupled algebraic Riccati equation, which can hardly be solved by mathematical methods directly. To solve this problem, an offline parallel hybrid learning algorithm is first designed, where system dynamics should be known as a prior. Furthermore, an online parallel $Q$ -learning hybrid learning algorithm is developed. The main characteristics of the proposed online hybrid learning algorithms are threefold: 1) system dynamics are avoided during the learning process; 2) compared with the policy iteration method, the restriction of the initial stable control policy is removed; and 3) compared with the value iteration method, a faster convergence rate can be obtained. Finally, we provide a tunnel diode circuit system model to validate the effectiveness of the present learning algorithm.

ABSTRACT This research presents results of the experimental and numerical study of Brazilian tests on cylindrical and cubic specimens made of autoclaved aerated concrete. Failure mechanisms are discussed based on [...]

Background: The effect of multidrug immunosuppressive protocols on the salivary glands is still unknown. This study aimed to determine the influence of immunosuppressive regimens based on calcineurin inhibitors (CNIs) and conversion to rapamycin on the morphology, apoptosis, and proliferation of rat salivary glands. Methods: Male rats received cyclosporin A (CsA), tacrolimus (FK-506), mycophenolate mofetil (MMF), rapamycin (Rapa), and prednisone (Pre) according to three-drug protocols: CMP (CsA, MMF, and Pre), CMP/R (CsA, MMF, and Pre with conversion to Rapa), TMP (FK-506, MMF, and Pre), and TMP/R (FK-506, MMF, and Pre with conversion to Rapa). Morphological and immunohistochemical and quantitative analyses of the salivary glands were performed. Results: Structural changes in salivary glands were observed in all experimental groups, especially in the submandibular gland. In the salivary glands, the percentages of collagen fibers and TUNEL-, Ki67- and PCNA-positive cells were higher in the experimental groups vs. the control but were lower in the CMP/R and TMP/R groups vs. the CMP and TMP groups, with the exception of collagen fibers in the parotid gland in the TMP/R group vs. the TMP group. Conclusions: Long-term administration of CNIs in triple regimens and after conversion to rapamycin monotherapy, causes morphological changes in the salivary glands of rats. Immunosuppressive treatment based on CNIs is associated with an increase in collagen accumulation. The effects of the conversion of treatment with CNIs to rapamycin in immunosuppressive protocols in rat salivary glands lead to decreased fibrosis, apoptosis, and proliferation. These changes may possibly prevent abnormalities resulting from the application of CNIs.

In this note, the control problem for discrete-time hidden semi-Markov jump systems is investigated under the situation that the system modes are unavailable directly. Compared with the previous results, the case when both system modes and states are immeasurable simultaneously is fully considered and an observer-based control scheme is established for discrete-time hidden semi-Markov jump systems. The random parameters of the systems are subject to a two-layer stochastic process and the underlying stochastic process is assumed to be subject to a semi-Markov process. Furthermore, a novel switched Lyapunov function is used, which may be monotonically increasing or decreasing at the instant of nonmodal switching. Moreover, by means of the stochastic stability theory and semi-Markov kernel method, some novel sufficient conditions ensuring $\sigma$-error mean-square stability of the closed-loop system are obtained by a power term reduction method. Finally, an illustrative example is introduced to verify the feasibility of the proposed control method.

The prevailing view in international jurisprudence is that no one can claim compensation for the fact of being alive. This view was developed based on so-called ‘wrongful life’ cases, in which, due to medical malpractice, parents were deprived of the opportunity to perform a legally permitted abortion, resulting in the birth of a disabled or unwanted child. A new chapter in this category of claims was opened by the case under review. The German Supreme Court took up what, in view of the ageing of Western societies, is a very topical and socially difficult issue of a son’s claim for damages for keeping his father alive. The ruling concerns a special category of civil claims so far not commented on in Polish literature or jurisprudence – ‘wrongful survival’. The German Supreme Court rejected the possibility of claiming compensation under German law for prolonging human existence, even if it involved suffering. Much of the reasoning of the Court is also applicable under Polish law. However, depending on the interpretation of the norms concerning the patient’s right to self-determination, the possibility of partial compensation for the costs of unlawfully keeping someone alive also seems to be acceptable under Polish law.

The acute occlusion of a peripheral bypass graft leads to acute limb ischemia (ALI) and threatens the viability of the limb if left untreated. The aim of the present study was to analyze the results of surgical and hybrid revascularization techniques for patients with ALI due to peripheral graft occlusions.

This article presents a decentralized learning control method for a class of partially unknown nonlinear systems with asymmetric control input constraints and mismatched interconnections via a novel dynamic event-triggering condition. By employing an integral reinforcement learning strategy, the system drift dynamics can be avoided in the learning process. Meanwhile, a critic neural network is designed to obtain the approximated value function and tuned by using the gradient descent approach. Furthermore, a novel dynamic event-triggering condition is designed to determine the occurrence of an event by introducing a dynamic variable. By using the Lyapunov theory, all signals in the closed-loop system are proved to be uniformly ultimately bounded. Finally, we present a nonlinear interconnected system and an interconnected power system to verify the effectiveness of the proposed method.