Radius Of Convergence Research Articles

Cancer-Specific Health Utilities: Evaluation of Core Measurement Properties of the EORTC QLU-C10D in Lung Cancer Patients-Data from Four Multicentre LUX-Lung Trials, Applying Six Country Tariffs.

Cost-utility analysis generally requires valid preference-based measures (PBMs) to assess the utility of patient health. While generic PBMs are widely used, disease-specific PBMs may capture additional aspects of health relevant for certain patient populations. This study investigates the construct and concurrent criterion validity of the cancer-specific European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Utility-Core 10 dimensions (QLU-C10D) in non-small-cell lung cancer patients. We retrospectively analysed data from four multicentre LUX-Lung trials, all of which had administered the EORTC Quality of Life Questionnaire (QLQ-C30) and the EQ-5D-3L. We applied six country-specific value sets (Australia, Canada, Italy, the Netherlands, Poland, and the United Kingdom) to both instruments. Criterion validity was assessed via correlations between the instruments' utility scores. Correlations of divergent and convergent domains and Bland-Altman plots investigated construct validity. Floor and ceiling effects were assessed. The comparison of the EORTC QLU-C10D and EQ-5D-3L produced homogenous results for five of the six country tariffs. High correlations of utilities (r > 0.7) were found for all country tariffs except for the Netherlands. Moderate to high correlations of converging domain pairs (r from 0.472 to 0.718) were found with few exceptions, such as the Social Functioning-Usual Activities domain pair (max. r = 0.376). For all but the Dutch tariff, the EORTC QLU-C10D produced consistently lower utility values compared to the EQ-5D-3L (x̄ difference from -0.082 to 0.033). Floor and ceiling effects were consistently lower for the EORTC QLU-C10D (max. 4.67% for utilities). The six country tariffs showed good psychometric properties for the EORTC QLU-C10D in lung cancer patients. Criterion and construct validity was established. The QLU-C10D showed superior measurement precision towards the upper and lower end of the scale compared to the EQ-5D-3L, which is important when cost-utility analysis seeks to measure health change across the severity spectrum.

Biogeochemical Fluxes of Nickel in the Global Oceans Inferred From a Diagnostic Model

AbstractNickel (Ni) is a micronutrient that plays a role in nitrogen uptake and fixation in the modern ocean and may have affected rates of methanogenesis on geological timescales. Here, we present the results of a diagnostic model of global ocean Ni fluxes which addresses key questions about marine Ni cycling. Sparsely available observations of Ni concentration are first extrapolated into a global gridded climatology using tracers with better observational coverage such as macronutrients, and testing three different machine learning techniques. The physical transport of Ni is then estimated using the ocean circulation inverse model (OCIM2), revealing regions of net convergence or divergence. These diagnostics are not based on any assumption about Ni biogeochemical cycling, but their spatial patterns can be used to infer where biogeochemical processes such as biological Ni uptake and regeneration take place. Although Ni and silicate (Si) have similar concentration patterns in the ocean, we find that the spatial pattern of Ni uptake in the surface ocean is similar to phosphate (P) uptake but not to silicate (Si) uptake. This suggests that their similar distributions arise from different biogeochemical mechanisms, consistent with other evidence showing that Ni is not incorporated into diatom frustules. We find that Ni:P ratios at uptake do not decrease as Ni concentrations approach 2 nM, which challenges the hypothesis of a ∼2 nM pool of non‐bioavailable Ni in the surface ocean. Finally, we find that the net regeneration of Ni occurs deeper in the ocean than for P, though not as deeply as for Si.

Performance analysis of a collision channel with abandonments

We consider a Markovian retrial queueing system with customer collisions and abandonment in the context of carrier-sense multiple access systems. Using z-transform techniques, we find a set of first-order differential equations for the probability generating functions of the orbit size when the server is empty, busy, or in the collision phase. We then rely on series expansion techniques to extract approximations for relevant performance measures from this set of differential equations. More precisely, we construct a numerical algorithm to calculate the terms in the series expansions of various factorial moments of the orbit size. To improve the accuracy of our series expansion approach, we apply Wynn’s epsilon algorithm which not only speeds up convergence, but also extends the region of convergence. We illustrate the accuracy of our approach by means of some numerical examples, and find that the method is both fast and accurate for a wide range of the parameter values.

THE DIFFERENTIAL EFFECTS OF CREDIT POLICY ON REAL ESTATE PRICES FROM THE PERSPECTIVE OF CLUB CONVERGENCE

This study investigates the differential effects of credit policy in the context of real estate price convergence in China. First, we analyze the real estate price convergence of 35 large and medium-sized cities in China using [Formula: see text] convergence and club convergence methods. Subsequently, based on the convergence situation, we use panel models to compare the heterogeneous effects of the credit policy regulation of different clubs. The findings are as follows. (1) In terms of overall convergence, the findings confirm that there is no [Formula: see text] convergence in China’s real estate prices. Prices in each city do not show a trend of convergence to the total mean. (2) There are currently four convergence clubs and one divergence group in terms of regional convergence. Cities with similar initial price levels have similar structural characteristics and tend to converge to their respective local steady states. GDP per capita and population density are the main driving forces for the formation of a real estate price convergence club. (3) We show that the credit scale has a statistically positive impact on the real estate price, and the credit scales of various convergence clubs have different effects on real estate prices. Clubs with more developed real estate and financial markets are more sensitive to changes in credit policy.

Inequality and poverty in Spain: Insights from a regional convergence analysis

AbstractWe study the dynamics of inequality and poverty across 17 Spanish regions during 2008–2021. Through a club convergence approach, the results show noticeable differences in both indicators, income inequality (S80/S20) and poverty rate: two clubs are endogenously derived from inequality, while the analysis of the poverty was conducted in four clubs. In addition, the results are complemented with the outcomes for the GDP per capita, where more heterogeneity is detected, with three clubs, but with six divergent regions. The ordered logit model allows to identify the driving factors of such clubs. Finally, policy implications are discussed: the findings recommend the need for specific public policies to address regional differences in terms of economic and social growth also considering the trajectories—convergence or divergence—in inequality and poverty and their determining factors.

Option pricing under jump diffusion model

We provide an European option pricing formula written in the form of an infinite series of Black–Scholes-type terms under double Lévy jumps model, where both the interest rate and underlying price are driven by Lévy processes. The series solution converges with a radius of convergence, and it is complemented by some numerical experiments to demonstrate its speed of convergence.

On the two-stage multisplitting iteration methods for linear complementarity problems

In this work, the two-stage multisplitting iteration methods based on the equivalent modulus equations are analyzed for solving linear complementarity problems. New convergence results are presented where the convergence domains of the parameter matrices are enlarged compared the existing literatures. Furthermore, the improved domains are validated by numerical examples with parallel computations using OpenACC.

Influence of variable fluid properties on mixed convective Darcy–Forchheimer flow relation over a surface with Soret and Dufour spectacle

Abstract The thermo-diffusion applications of nanofluid subject to variable thermal sources have been presented. The significance of Darcy–Forchheimer effects is attributed. The flow comprises the mixed convection and viscous dissipation effects. Furthermore, the variable influence of viscosity, thermal conductivity, and mass diffusivity is treated to analyze the flow. The analysis of problem is referred to convective mass and thermal constraints. The analytical simulations are proceeded with homotopy analysis method. The convergence region is highlighted. Novel physical contribution of parameters is visualized and treated graphically. It is noted that larger Brinkman number leads to improvement in heat transfer. The concentration pattern boosted due to Soret number. The wall shear force enhances with Hartmann number and variable thermal conductivity coefficient.

Quantum biochemical analysis of the TtgR regulator and effectors

The recent expansion of multidrug-resistant (MDR) pathogens poses significant challenges in treating healthcare-associated infections. Although antibacterial resistance occurs by numerous mechanisms, active efflux of the drugs is a critical concern. A single species of efflux pump can produce a simultaneous resistance to several drugs. One of the best-studied efflux pumps is the TtgABC: a tripartite resistance-nodulation-division (RND) efflux pump implicated in the intrinsic antibiotic resistance in Pseudomonas putida DOT-T1E. The expression of the TtgABC gene is down-regulated by the HTH-type transcriptional repressor TtgR. In this context, by employing quantum chemistry methods based on the Density Functional Theory (DFT) within the Molecular Fragmentation with Conjugate Caps (MFCC) approach, we investigate the coupling profiles of the transcriptional regulator TtgR in complex with quercetin (QUE), a natural polyphenolic flavonoid, tetracycline (TAC), and chloramphenicol (CLM), two broad-spectrum antimicrobial agents. Our quantum biochemical computational results show the: [i] convergence radius, [ii] total binding energy, [iii] relevance (energetically) of the ligands regions, and [iv] most relevant amino acids residues of the TtgR-QUE/TAC/CLM complexes, pointing out distinctions and similarities among them. These findings improve the understanding of the binding mechanism of effectors and facilitate the development of new chemicals targeting TtgR, helping in the battle against the rise of resistance to antimicrobial drugs. These advances are crucial in the ongoing fight against rising antimicrobial drug resistance, providing hope for a future where healthcare-associated infections can be more beneficially treated.

Characteristics of self-medication assessment instruments in Brazil: an integrative review

Objective: To describe the characteristics of self-medication assessment instruments with evidence of validity in Brazil. Methods: An integrative review, without temporal delimitation, with collection in the LILACS, Scopus, PubMed, MEDLINE and Web of Science databases. Ten studies related to five instruments were included. Results: The most convergent domains were sociodemographic aspects, self-medication practice, reasons, medications used and recommendation/sources. Self-medication was assessed by only one instrument with evidence of validity, but it was multidimensional, making its application difficult. The instruments showed good reliability indices, however, of the five, one did not measure reliability. The good psychometric properties of the self-medication and temporomandibular pain instrument stand out (Kappa: 0.810, Cronbach’s alpha: 0.844). Conclusion: The different instruments analyzed present limitations in evidence of validity, showing the need to develop an instrument focused on self-medication that is reliable and valid.

An Empirical Analysis of Racial Segregation in Higher Education

Abstract This paper documents how segregation between Black students and White students across U.S. colleges has evolved since the 1960s, explores potential channels through which changes occur, and studies segregation across majors within colleges. The main findings are: (1) Black–White dissimilarity fell sharply in the late 1960s and early 1970s and has fallen more gradually since then. White students' exposure to Black students rose almost continuously from 1968 through 2011 before declining somewhat in recent years. Meanwhile, Black students' exposure to White students increased sharply in the late 1960s and early 1970s and has fluctuated since. (2) There has been regional convergence, although colleges in the South remain more segregated than those in any other region when measured by dissimilarity or by Black students' exposure to White students. (3) A major channel for the decline in segregation is the declining share of Black students attending historically Black colleges and universities. Differences in which U.S. state students attend college play only a small role in creating segregation, and there is moderate evidence that segregation is related to college selectivity stratification by race. (4) Although there is segregation within universities, most segregation across major × university cells occurs across universities.

Self-similar solutions to a multidimensional singular heat equation with power nonlinearity

The paper deals with the construction of exact solutions to a singular heat equation with power nonlinearity in the case of numerous independent variables with spatial (e.g. axial or central) symmetry. A new class of self-similar solutions is proposed, which reduce to solving the Cauchy problem for a second-order nonlinear ordinary differential equation having singularities at the higher derivative with respect to the required function and/or the independent variable. The ordinary differential equation is studied in two ways: analytically and numerically. The analytical study uses a truncated Taylor series with recurrently computed coefficients, for which explicit formulas are obtained. The numerical solution to the problem uses an iteration algorithm based on the collocation method and radial basis functions. The numerical analysis shows the convergence of the proposed numerical algorithm and its sufficient accuracy enabling one to use the found self-similar solutions to verify approximate solutions to the original heat equation. Besides, the numerical analysis has allowed the radius of convergence of the constructed Taylor series to be evaluated. The form of the constructed self-similar solutions, namely their unboundedness near the symmetry center (axis), enables us to study the behavior and exactness of the numerical solutions to the nonlinear singular parabolic-type equation that have been obtained by the stepwise solution method proposed by us earlier and possess the same property.

Resilient event-triggered observer-based control of non-linear systems under denial-of-service attacks with actuator saturation

This paper studies the control problem for a continuous-time networked system with non-linearity in the state equation as well as in the input, as saturation. The system is considered under denial-of-service (DoS), attacks which cause the blockage of input and/or output components in the overall closed-loop model. An event-triggering scheme that is resilient in nature, along with an observer-based control, has been considered under DoS attacks. The resultant scheme ensures efficient network resources and excludes Zeno behavior naturally due to the presence of a minimum positive interevent delay. Then, an event-based switched non-linear model is presented to address both the event-triggering scheme and the presence of DoS blocking attacks. A piece-wise Lyapunov–Krasovskii functional method on the described non-linear model, resulting in the switched system, is considered for achieving an exponentially stable response by driving the required feasibility conditions. In the presence of a non-linear system with saturation in the actuator, the presented design establishes quantitative relationships among the exponential decay rate, active/sleeping intervals of attacks, parameters of the event-triggering condition, and sampling period of the system. After that, linear matrix inequalities are presented for designing an event-triggered controller with an observer, while the design also includes the region of convergence for dealing with the input non-linearity. Finally, comparative results for an offshore structure model with non-linearity in states as well as in actuator, are demonstrated to verify the results of the control scheme that is developed. It has been verified that our design is less conservative than the previous designs, and can handle the non-linearities in the dynamics of plant and actuator saturation more efficiently, while DoS attacks are also present. By applying our proposed method, the overshoot and undershoot are less than ±2.5 percent, while system states converge to the origin within 55 s.

Modified Nested Saturated Control for Uncertain Multiple Integrators With High-Order Nonlinear Perturbation.

This article studies the global asymptotic stability problem of multiple integrators subject to uncertain parameters and high-order nonlinear perturbation. By introducing a modified saturation function with positive tunable parameters, three types of modified nested saturated controllers with different parameter assignments are proposed to handle the uncertain integrators with high-order nonlinear perturbation. The specific mechanism of the modified nested saturated controllers with different parameter assignments, in which control parameters appear before states, saturation functions, or saturation levels, is comprehensively analyzed. With the help of a modified saturation function, the global convergence domain of each state can be kept invariable in the saturation reduction analysis. Meanwhile, a large saturation level is obtained by adjusting positive tunable parameters. Combining with derivatives calculation and M -matrix-based comparison theory, proposed saturated control schemes are utilized to handle the considered system. Finally, an active magnetic bearing (AMB) system is revisited as an uncertain mechanical system and used to verify the feasibility of the proposed control designs.

Fractional Approach for Belousov-Zhabotinsky Reactions Model with Unified Technique

The Belousov-Zhabotinsky reaction model represents chemical oscillators that exhibit periodic vibrations as a result of complex physic-chemical phenomena. The non-linear behaviour exhibited by Belousov-Zhabotinsky model is the cause of Turing patterns, birth of spiral waves, rise of limit cycle attractors, and deterministic chaos in many chemical reaction processes. Due to these noteworthy characteristics, in this paper, we have analyzed mathematical Belousov-Zhabotinsky model by a novel numerical approach q-Homotopy analysis transformation method. To interpret new observations, we have incorporated Caputo fractional derivative in the model. The numerical result are presented graphically and concerning the absolute error of solutions. With the help of the homotopy parameter curve, we have projected the convergence region with reference to diverse values of fractional derivative. This work establishes that the projected numerical algorithm is a well-organized tool to analyze the multifaceted coupled partial differential equation representing Belousov-Zhabotinsky type reactions.

Modeling and analysis of the triple diffusion unsteady flow of couple stress nanofluid with variable viscosity and distinct thermal sources

Thanks to their optimal thermal characteristics, nanomaterials stand out for their varied applications in heat transfer systems, energy storage, industrial processes, and biomedical research. Recently, scientists explored various dynamic properties in nanofluid flow to develop an even better thermal model. In this context, the phenomenon of triple diffusion in nanofluids constitutes an active area of research, offering promising applications in nanotechnology, metallurgical processes, chemical reactors, and thermo-diffusion processes. This paper analyzes the triple diffusion flow of a torque-constrained nanofluid, induced by a periodically oscillating porous surface, taking into account the importance of variations in thermal consequences. The viscosity of the torque-constrained nanofluid is assumed to be temperature-dependent. The analysis takes into account the variable role of thermal conductivity, mass diffusivity, and solute volume fraction. The modeling of the problem is expressed by coupled nonlinear partial differential equations. The semi-analytic technique, known as the homotopic analysis scheme, is used for resolution. The solution is validated and confirms the convergence region. The physical aspects of the parameters are examined with regard to the parameters involved. The simulated observations reveal that with the Dufour–Lewis factor and varying mass diffusivity, an increase in solute concentration is seen. The concentration of nanoparticles decreases with the nano-Lewis number.

Discovery of Eclogite Facies Kyanite Quartzite in Central Jilin Province:Evidence of Ultra-high-pressure Metamorphism

The work area is located in the convergence domain of the Siberian plate and North China plate. The Jilin Province of the Soren-Xilamnlun river-Changchun-Heilog jiang plate collision zone. Before 2000, there was no empirical evidence of high-ultrahigh pressure transformation in the middle Jilin section. For this reason, the Changchun-Panshi-Jiaohe area was selected as the primary geological survey area. After comprehensively analysing the previous regional geological and mineral exploration data, we drew on the experience and achievements of studying the collision between the Suiu-dabie plate. Jiaohe blueschist origin was concerned. After fine field investigation, collecting fresh and representative samples, conducting microscopic identification, electron probe analysis and other work, the key identification and measurement results were obtained. Comprehensive results proved that the geological body producing kyanite undergoes high-pressure kyanite-quartzite was a metamorphic rock of gernet pgroxenite facies. This discovery is of fundamental importance for the establishment of the Jihei high pressure human ultra-high-pressure collision subduction zone. The discovery was briefly reported in 2000 and is now being published in detail. The garnet-phase blueschist quartzite is massive, laminated, ienticular, and rootless hook like bodies occur in within the luoguangou Dashihu narrow ductile shear zone. The rock being sheared is late paleozoic Early perntian Daheshan formation and late variscan Granite Porphyry, which were deformed and metamorphosed to form. blueschist dolomite quartz schist and dolomitic blueschist quartzite. The Peak mineral combination is Ky2+Qz2+Ms2 (Phn2) +Zt+Rt+Miss, without Sili and Pl, which basically meets the constraining charactenstics of eciogite facies. The peak metamorphic temperature reaches 700-750℃, indicating the Si (pfu) =3. 440-3. 535 of phengite, and indicated metamorphic pressure reaches p=2. 75-3. 30GPa, which shows that the rock has undergone ultra-high pressure metamorphic process, and its temperature and pressure conditions have been comparable to those formed by coesite. The temperature of secondary peak period of is about 550℃-600℃ and the pressure is about 1. 6-1. 7GPa. The multi-phase nature of the blueschist, muscovite and quartz indicates that the rock is subjected to prosess of subduction exhumation, and exhumation suffering from strong progressional and retrograde metamorphism. The temperature and pressure numbers of the metamorphism indicate that the paths are successively hornblende and green schist phases, with temperatures of about 500℃-450℃ and pressures of about 0. 5-0. 7GPa, and temperatures of about 300℃-350℃ and pressures of about 0. 3-0. 4GPa, respectively.

Economic convergence in the European Union at the regional level with particular attention to the impact of the COVID-19 pandemic – a spatio-temporal approach

The study presents an analysis of the impact of the COVID-19 pandemic on the economic convergence in the European Union (EU). It is widely known that every crisis can have a negative influence on the economic development of a country or region. This research analysed data for 233 EU regions on the NUTS-2 level in the years 2000-2020.analyzed To verify the occurrence of the convergence process, the spatio-temporal β-convergence models for pooled time series and cross-sectional data (TSCS) were estimated. Expandingthe convergence models with the dummy variables characterising two critical crises in the analysed period (the global financial crisis in 2007-2009 and the start of the COVID-19 pandemic in 2020) allowed us to verify their impact on the regional convergence processin the EU. The main aim of this research is to assess the influence of presented crises on the economic convergence between EU regions. Because regions cooperate, the spatial element of the β-convergence models was also included. The additional aspect of the study is the comparison of the differences in strength of the influence of the mentioned crises on economic convergence.

On the analytic extension of the Horn's hypergeometric function $H_4$

The paper establishes new convergence domains of branched continued fraction expansions of Horn's hypergeometric function $H_4$ with real and complex parameters. These domains enabled the PC method to establish the analytical extension of analytical functions to their expansions in the studied domains of convergence. A few examples are provided at the end to illustrate this.

The Dynamics of Regional Inequalities in Romania. Comparative Analysis between the major Crises – Financial and Sanitary

In Romania, the issue of economic inequalities and regional convergence is one of the current important topics on which the attention of economic specialists and the decision-making factors is focused. In the actual context, the regional policy in Romania is implemented at regional level, the regions being formed by counties that have voluntarily associated on the basis of a convention signed by the representatives of the County Councils, respectively of the General Council of Bucharest. After the year 2000, the development regions faced two major crises: the global financial crisis (2008-2009) and the one caused by the COVID-19 pandemic (2020-2021). Both crises have caused important effects at regional level and both have been supported by a number of territorial strategies and policies, to which there was added the cohesion and regional development policy financed by the EU Structural Funds. The paper is based on the analysis of the differences between the regions of Romania, in the period 2008-2022, during the COVID-19 pandemic, by highlighting the differences between the dynamics of certain indicators, of the analysis of the GINI coefficients for measuring inequalities, trying to answer the question which of the two crises, financial or health, affected the level of territorial inequalities more and what was the evolution of the regions of Romania in these two sub-periods. Regarding the financial crisis versus the pandemic one, in the majority of the indicators, it was shown that the values of the Gini coefficients in the 2020-2022 were higher than the ones in 2008-2010 and also after the COVID-19 crisis the tendency of increased disparities was maintained. The only domains that were least affected by the pandemic were demography (rural population), transportation infrastructure and economic potential (companies with 10-49 employees).