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1.
Proc Natl Acad Sci U S A ; 121(22): e2401656121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38787880

RESUMO

Understanding the dynamics of electric-double-layer (EDL) charging in porous media is essential for advancements in next-generation energy storage devices. Due to the high computational demands of direct numerical simulations and a lack of interfacial boundary conditions for reduced-order models, the current understanding of EDL charging is limited to simple geometries. Here, we present a network model to predict EDL charging in arbitrary networks of long pores in the Debye-Hückel limit without restrictions on EDL thickness and pore radii. We demonstrate that electrolyte transport is described by Kirchhoff's laws in terms of the electrochemical potential of charge (the valence-weighted average of the ion electrochemical potentials) instead of the electric potential. By employing the equivalent circuit representation suggested by these modified Kirchhoff's laws, our methodology accurately captures the spatial and temporal dependencies of charge density and electric potential, matching results obtained from computationally intensive direct numerical simulations. Our network model provides results up to six orders of magnitude faster, enabling the efficient simulation of a triangular lattice of five thousand pores in 6 min. We employ the framework to study the impact of pore connectivity and polydispersity on electrode charging dynamics for pore networks and discuss how these factors affect the time scale, energy density, and power density of capacitive charging. The scalability and versatility of our methodology make it a rational tool for designing 3D-printed electrodes and for interpreting geometric effects on electrode impedance spectroscopy measurements.

2.
Entropy (Basel) ; 25(11)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37998175

RESUMO

We formulate the first law of global thermodynamics for stationary states of the ideal gas in the gravitational field subjected to heat flow. We map the non-uniform system (described by profiles of the density and temperature) onto the uniform one and show that the total internal energy U(S*,V,N,L,M*) is the function of the following parameters of state: the non-equilibrium entropy S*, volume V, number of particles, N, height of the column L along the gravitational force, and renormalized mass of a particle M*. Each parameter corresponds to a different way of energy exchange with the environment. The parameter M* changes internal energy due to the shift of the centre of mass induced by the heat flux. We give analytical expressions for the non-equilibrium entropy S* and effective mass M*. When the heat flow goes to zero, S* approaches equilibrium entropy. Additionally, when the gravitational field vanishes, our fundamental relation reduces to the fundamental relation at equilibrium.

3.
Entropy (Basel) ; 25(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37998197

RESUMO

In this paper, we formulate the first law of global thermodynamics for stationary states of the binary ideal gas mixture subjected to heat flow. We map the non-uniform system onto the uniform one and show that the internal energy U(S*,V,N1,N2,f1*,f2*) is the function of the following parameters of state: a non-equilibrium entropy S*, volume V, number of particles of the first component, N1, number of particles of the second component N2 and the renormalized degrees of freedom. The parameters f1*,f2*, N1,N2 satisfy the relation (N1/(N1+N2))f1*/f1+(N2/(N1+N2))f2*/f2=1 (f1 and f2 are the degrees of freedom for each component respectively). Thus, only 5 parameters of state describe the non-equilibrium state of the binary mixture in the heat flow. We calculate the non-equilibrium entropy S* and new thermodynamic parameters of state f1*,f2* explicitly. The latter are responsible for heat generation due to the concentration gradients. The theory reduces to equilibrium thermodynamics, when the heat flux goes to zero. As in equilibrium thermodynamics, the steady-state fundamental equation also leads to the thermodynamic Maxwell relations for measurable steady-state properties.

4.
J Chem Phys ; 159(19)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37982484

RESUMO

Equilibrium thermodynamics describes the energy exchange of a body with its environment. Here, we describe the global energy exchange of an ideal gas in the Coutte flow in a thermodynamic-like manner. We derive a fundamental relation between internal energy as a function of parameters of state. We analyze a non-equilibrium transition in the system and postulate the extremum principle, which determines stable steady states in the system. The steady-state thermodynamic framework resembles equilibrium thermodynamics.

5.
Entropy (Basel) ; 25(9)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37761594

RESUMO

There is a long-standing question of whether it is possible to extend the formalism of equilibrium thermodynamics to the case of nonequilibrium systems in steady-states. We have made such an extension for an ideal gas in a heat flow. Here, we investigated whether such a description exists for the system with interactions: the van der Waals gas in a heat flow. We introduced a steady-state fundamental relation and the parameters of state, each associated with a single way of changing energy. The first law of nonequilibrium thermodynamics follows from these parameters. The internal energy U for the nonequilibrium states has the same form as in equilibrium thermodynamics. For the van der Waals gas, U(S*,V,N,a*,b*) is a function of only five parameters of state (irrespective of the number of parameters characterizing the boundary conditions): the effective entropy S*, volume V, number of particles N, and rescaled van der Waals parameters a*, b*. The state parameters, a*, b*, together with S*, determine the net heat exchange with the environment. The net heat differential does not have an integrating factor. As in equilibrium thermodynamics, the steady-state fundamental equation also leads to the thermodynamic Maxwell relations for measurable steady-state properties.

6.
Med Sci Monit ; 29: e939169, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37553822

RESUMO

BACKGROUND The health sector in Poland is currently facing challenges such as limited financial resources, poor infrastructure, and insufficient human resources. To address these issues, increasing cost-effectiveness at the individual physician level has become essential. This study aimed to evaluate the efficiency and effectiveness of patient care at the level of individual primary health care physicians and to compare the performance of physicians working in urban and rural areas. MATERIAL AND METHODS Thirteen original effectiveness indicators were developed based on a literature review, expert consultations, and a pilot study at the Medical and Diagnostic Center in Siedlce. The indicators were used to evaluate the effectiveness of physicians and compare physicians' characteristics working in rural and urban areas. The study extracted data on physicians' characteristics and used the indicators to evaluate their effectiveness. RESULTS Physicians working in rural areas treated more patients due to staff shortages. However, physicians working in urban areas demonstrated greater effectiveness in performing routine and advanced health checks and mammograms. Despite this advantage, the average life expectancy of patients was higher among patients of physicians working in rural areas. CONCLUSIONS Five indicators developed in the study formed a scale, which is a step toward developing a uniform effectiveness indicator. Further research on consistently measuring effectiveness could significantly impact the development of sociometric research methodology. This study highlights the differences in efficiency and effectiveness of physicians working in rural vs urban areas and underscores the need for healthcare policymakers to consider these differences in addressing healthcare resource allocation.


Assuntos
Médicos , Serviços de Saúde Rural , Humanos , Polônia , Projetos Piloto , Assistência ao Paciente , População Rural
7.
Environ Dev Sustain ; : 1-36, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37362984

RESUMO

The aim of the article is to analyse the factors influencing entrepreneurs' decisions about investing in renewable energy. It outlines a number of different factors that may affect the process of transforming entrepreneurs into business prosumers, who thus want to limit the effects of rising energy prices. The article defends the thesis that in addition to the economic, technological and psychological dimensions, legal and political stability, access to reliable information and the level of trust in a given society are equally important. Based on the quantitative research results, the article indicates which elements are particularly important for entrepreneurs when making decisions about investing in renewable energy and which institutions are indicated by Polish entrepreneurs as responsible for implementing energy transition. The article also indicates that information about the possibility of receiving funding from the European Union and the government, the government's energy policy and technological possibilities is important for entrepreneurs' decisions about investing in renewable energy in Poland. It is always difficult to implement sustainable development goals without an atmosphere of trust and predictable legal stability in which entrepreneurs can run their businesses. Supplementary Information: The online version contains supplementary material available at 10.1007/s10668-023-03400-z.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36900836

RESUMO

BACKGROUND: Poland is witnessing a migration crisis caused by the ongoing military conflict in Ukraine. In addition to housing and necessities, 1.8 million Ukrainians that had taken refuge in Poland must have access to medical care. We aim to propose a strategy for implementing the changes in the Polish health care system in response to the Ukrainian refugee crisis. METHODS: A literature review on organizational changes in the functioning of health care systems during the migration crises worldwide in recent years and brainstorming in order to develop a strategy for implementing changes in the Polish health care system in response to the Ukrainian refugee crisis. RESULTS: The proposed strategy for implementing the changes in the Polish health care system is based on building health care resilience and adaptation to different crises. The operational objectives of organization-related activities are: (1) preparation of medical facilities to provide help for refugees, (2) development and implementation of the communication system, (3) implementation of available digital solutions, (4) organization of the diagnostic and medical services, (5) and implementation of changes in the management of medical facilities. CONCLUSIONS: Urgent reorganization is required to respond to an unavoidable increase in the demand for health care services.


Assuntos
Militares , Refugiados , Humanos , Polônia , Ucrânia , Atenção à Saúde
10.
J Chem Phys ; 157(19): 194108, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414440

RESUMO

There is a long-standing question as to whether and to what extent it is possible to describe nonequilibrium systems in stationary states in terms of global thermodynamic functions. The positive answers have been obtained only for isothermal systems or systems with small temperature differences. We formulate thermodynamics of the stationary states of the ideal gas subjected to heat flow in the form of the zeroth, first, and second law. Surprisingly, the formal structure of steady state thermodynamics is the same as in equilibrium thermodynamics. We rigorously show that U satisfies the following equation dU = T*dS* - pdV for a constant number of particles, irrespective of the shape of the container, boundary conditions, the size of the system, or the mode of heat transfer into the system. We calculate S* and T* explicitly. The theory selects stable nonequilibrium steady states in a multistable system of ideal gas subjected to volumetric heating. It reduces to equilibrium thermodynamics when heat flux goes to zero.

11.
Nat Commun ; 13(1): 6451, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307412

RESUMO

The reaction kinetics between like-charged compounds in water is extremely slow due to Coulomb repulsions. Here, we demonstrate that by screening these interactions and, in consequence, increasing the local concentration of reactants, we boost the reactions by many orders of magnitude. The reaction between negatively charged Coenzyme A molecules accelerates ~5 million-fold using cationic micelles. That is ~104 faster kinetics than in 0.5 M NaCl, although the salt is ~106 more concentrated. Rate enhancements are not limited to micelles, as evidenced by significant catalytic effects (104-105-fold) of other highly charged species such as oligomers and polymers. We generalize the observed phenomenon by analogously speeding up a non-covalent complex formation-DNA hybridization. A theoretical analysis shows that the acceleration is correlated to the catalysts' surface charge density in both experimental systems and enables predicting and controlling reaction rates of like-charged compounds with counter-charged species.


Assuntos
Micelas , Água , Polímeros , Cátions , Cinética , Cloreto de Sódio
12.
Phys Rev E ; 105(5-1): 054133, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35706157

RESUMO

We investigate the thermal relaxation of an ideal gas from a nonequilibrium stationary state. The gas is enclosed between two walls, which initially have different temperatures. After making one of the walls adiabatic, the system returns to equilibrium. We notice two distinct modes of heat transport and associated timescales: one connected with a traveling heat front and the other with internal energy diffusion. At the heat front, which moves at the speed of sound, pressure, temperature, and density change abruptly, leaving lower values behind. This is unlike a shock wave, a sound wave, or a thermal wave. The front moves multiple times between the walls and is the dominant heat transport mode until surpassed by diffusion. We found that it can constitute an order 1 factor in shaping the dynamics of the outflow of internal energy. We found that cooling such a system is quicker than heating, and that hotter bodies cool down quicker than colder ones. The latter is known as the Mpemba effect.

13.
Soft Matter ; 18(1): 198-213, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34870312

RESUMO

Porous electrodes are found in energy storage devices such as supercapacitors and pseudocapacitors. However, the effect of electrode-pore-size distribution on their energy storage properties remains unclear. Here, we develop a model for the charging of electrical double layers inside a cylindrical pore for arbitrary pore size. We assume small applied potentials and perform a regular perturbation analysis to predict the evolution of electrical potential and ion concentrations in both the radial and axial directions. We validate our perturbation model with direct numerical simulations of the Poisson-Nernst-Planck equations, and obtain quantitative agreement between the two approaches for small and moderate potentials. Our analysis yields two main characteristic features of arbitrary pore size: (i) a monotonic decrease of the charging timescale with an increase in relative pore size (pore size relative to Debye length); (ii) large potential changes for overlapping double layers in a thin transition region, which we approximate mathematically by a jump discontinuity. We quantify the contributions of electromigration and charge diffusion fluxes, which provide mechanistic insights into the dependence of charging timescale and capacitance on pore size. We develop a modified transmission circuit model that captures the effect of arbitrary pore size and demonstrate that a time-dependent transition-region resistor needs to be included in the circuit. We also derive phenomenological expressions for average effective capacitance and charging timescale as a function of pore-size distribution. We show that the capacitance and charging timescale increase with smaller average pore sizes and with smaller polydispersity, resulting in a gain of energy density at a constant power density. Overall, our results advance the mechanistic understanding of electrical-double-layer charging.

14.
Pol Merkur Lekarski ; 49(294): 405-410, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34919082

RESUMO

In Poland, there is a niche that can be filled with original research in the area of performance indicators of individual health care professionals. AIM: The aim of the study was the empirical verification of original effectiveness indicators and the identification of the degree of patient care effectiveness of selected primary health care professionals with the application of the developed indicators. MATERIALS AND METHODS: The study population consisted of physicians employed in the primary care in Medical and Diagnostic Centre (MDC) in Siedlce, Poland. The final study sample consisted of 29 respondents. 14 original indicators in three areas: structure, process and effect were developed and verified. RESULTS: The distribution of indicator values for the physicians included in the study demonstrated a diverse level of their effectiveness. The factor analysis performed for the 14 original indicators demonstrated that a highly reliable scale can be created out of 5 of the original indicators. CONCLUSIONS: In our pilot study we assessed the reliability of the designed tools. However, unfortunately, our research did not offer the opportunity to identify any dependencies of variables. A study on a larger sample of physicians would therefore be needed.


Assuntos
Médicos , Atenção Primária à Saúde , Humanos , Assistência ao Paciente , Projetos Piloto , Reprodutibilidade dos Testes
15.
Analyst ; 146(23): 7131-7143, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34726203

RESUMO

Quantitative description of biochemical processes inside living cells and at single-molecule levels remains a challenge at the forefront of modern instrumentation and spectroscopy. This paper demonstrates such single-cell, single-molecule analyses performed to study the mechanism of action of olaparib - an up-to-date, FDA-approved drug for germline-BRCA mutated metastatic breast cancer. We characterized complexes formed with PARPi-FL - fluorescent analog of olaparib in vitro and in cancer cells using the advanced fluorescent-based method: Fluorescence Correlation Spectroscopy (FCS) combined with a length-scale dependent cytoplasmic/nucleoplasmic viscosity model. We determined in vitro olaparib-PARP1 equilibrium constant (6.06 × 108 mol L-1). In the cell nucleus, we distinguished three states of olaparib: freely diffusing drug (24%), olaparib-PARP1 complex (50%), and olaparib-PARP1-RNA complex (26%). We show olaparib accumulation in 3D spheroids, where intracellular concentration is twofold higher than in 2D cells. Moreover, olaparib concentration was tenfold higher (506 nmol L-1vs. 57 nmol L-1) in cervical cancer (BRCA1 high abundance) than in breast cancer cells (BRCA1 low abundance) but with a lower toxic effect. Thus we confirmed that the amount of BRCA1 protein in the cells is a better predictor of the therapeutic effect of olaparib than its penetration into cancer tissue. Our single-molecule and single-cell approach give a new perspective of drug action in living cells. FCS provides a detailed in vivo insight, valuable in drug development and targeting.


Assuntos
Fenômenos Bioquímicos , Inibidores de Poli(ADP-Ribose) Polimerases , Imagem Individual de Molécula , Linhagem Celular Tumoral , Reparo do DNA , Humanos , Ftalazinas , Piperazinas , Poli(ADP-Ribose) Polimerase-1 , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
16.
Phys Rev E ; 104(2-1): 024102, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34525565

RESUMO

We discovered an out-of-equilibrium transition in the ideal gas between two walls, divided by an inner, adiabatic, movable wall. The system is driven out-of-equilibrium by supplying energy directly into the volume of the gas. At critical heat flux we have found a continuous transition to the state with a low-density, hot gas on one side of the movable wall and a dense, cold gas on the other side. Molecular dynamic simulations of the soft-sphere fluid confirm the existence of the transition in the interacting system. We introduce a stationary state Helmholtz-like function whose minimum determines the stable positions of the internal wall. This transition can be used as a paradigm of transitions in stationary states and the Helmholtz-like function as a paradigm of the thermodynamic description of these states.

17.
J Chem Phys ; 154(12): 124905, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33810690

RESUMO

Inclusion of hydrodynamic interactions is essential for a quantitatively accurate Brownian dynamics simulation of colloidal suspensions or polymer solutions. We use the generalized Rotne-Prager-Yamakawa (GRPY) approximation, which takes into account all long-ranged terms in the hydrodynamic interactions, to derive the complete set of hydrodynamic matrices in different geometries: unbounded space, periodic boundary conditions of Lees-Edwards type, and vicinity of a free surface. The construction is carried out both for non-overlapping as well as for overlapping particles. We include the dipolar degrees of freedom, which allows one to use this formalism to simulate the dynamics of suspensions in a shear flow and to study the evolution of their rheological properties. Finally, we provide an open-source numerical package, which implements the GRPY algorithm in Lees-Edwards periodic boundary conditions.

18.
Phys Rev Lett ; 125(7): 076001, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32857551

RESUMO

The charging of electrical double layers inside a cylindrical pore has applications to supercapacitors, batteries, desalination and biosensors. The charging dynamics in the limit of thin double layers, i.e., when the double layer thickness is much smaller than the pore radius, is commonly described using an effective RC transmission line circuit. Here, we perform direct numerical simulations (DNS) of the Poisson-Nernst-Planck equations to study the double layer charging for the scenario of overlapping double layers, i.e., when the double layer thickness is comparable to the pore radius. We develop an analytical model that accurately predicts the results of DNS. Also, we construct a modified effective circuit for the overlapping double layer limit, and find that the modified circuit is identical to the RC transmission line but with different values and physical interpretation of the capacitive and resistive elements. In particular, the effective surface potential is reduced, the capacitor represents a volumetric current source, and the charging timescale is weakly dependent on the ratio of the pore radius and the double layer thickness.

19.
Phys Rev Lett ; 125(5): 056001, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32794889

RESUMO

Two oppositely charged surfaces separated by a dielectric medium attract each other. In contrast we observe a strong repulsion between two plates of a capacitor that is filled with an aqueous electrolyte upon application of an alternating potential difference between the plates. This long-range force increases with the ratio of diffusion coefficients of the ions in the medium and reaches a steady state after a few minutes, which is much larger than the millisecond timescale of diffusion across the narrow gap. The repulsive force, an order of magnitude stronger than the electrostatic attraction observed in the same setup in air, results from the increase in osmotic pressure as a consequence of the field-induced excess of cations and anions due to lateral transport from adjacent reservoirs.

20.
Health Care Women Int ; 41(10): 1101-1110, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32238108

RESUMO

The authors of the article describe barriers in access to gynaecological care in Poland and compare them to problems of health care encountered by women in other developing countries. The authors defend the thesis that in periphery and semi-periphery societies, despite some local differences, women from rural areas have similar obstacles to access to care in health centers. At the same time, they emphasize that the spatial distance between women from rural areas and urban health centers usually goes hand in hand with other social obstacles: economic, cultural and ideological pressure.


Assuntos
Exame Ginecológico , Acessibilidade aos Serviços de Saúde , Serviços de Saúde Materna , Serviços de Saúde da Mulher , Adulto , Atenção à Saúde/organização & administração , Feminino , Humanos , Polônia , Política , População Rural , Fatores Socioeconômicos , População Urbana
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