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1.
Membranes (Basel) ; 14(7)2024 Jul 09.
Article in English | MEDLINE | ID: mdl-39057659

ABSTRACT

The escalating emissions of CO2 into the atmosphere require the urgent development of technologies aimed at mitigating environmental impacts. Among these, aqueous amine solutions and polymeric membranes, such as cellulose acetate and polyimide are commercial technologies requiring improvement or substitution to enhance the economic and energetic efficiency of CO2 separation processes. Ionic liquids and poly(ionic liquids) (PILs) are candidates to replace conventional CO2 separation technologies. PILs are a class of materials capable of combining the favorable gas affinity exhibited by ionic liquids (ILs) with the processability inherent in polymeric materials. In this context, the synthesis of the IL GLYMIM[Cl] was performed, followed by ion exchange processes to achieve GLYMIM variants with diverse counter anions (NTf2-, PF6-, and BF4). Subsequently, PIL membranes were fabricated from these tailored ILs and subjected to characterization, employing techniques such as SEC, FTIR, DSC, TGA, DMA, FEG-SEM, and CO2 sorption analysis using the pressure decay method. Furthermore, permeability and ideal selectivity assessments of CO2/CH4 mixture were performed to derive the diffusion and solubility coefficients for both CO2 and CH4. PIL membranes exhibited adequate thermal and mechanical properties. The PIL-BF4 demonstrated CO2 sorption capacities of 33.5 mg CO2/g at 1 bar and 104.8 mg CO2/g at 10 bar. Furthermore, the PIL-BF4 membrane exhibited permeability and ideal (CO2/CH4) selectivity values of 41 barrer and 44, respectively, surpassing those of a commercial cellulose acetate membrane as reported in the existing literature. This study underscores the potential of PIL-based membranes as promising candidates for enhanced CO2 capture technologies.

2.
Porto Alegre; Editora Rede Unida; jun. 2023. 189 p.
Monography in Portuguese | LILACS | ID: biblio-1437747

ABSTRACT

O livro Ciência da Palhaçaria: estudos teóricos e práticas em saúde mental aborda no campo da saúde possibilidades de pensar cientificamente a arteterapia, principalmente da palhaçaria. O nariz vermelho do palhaço simboliza o potencial aplicado da arte na saúde mental. Deste modo, apresentamos vários trabalho sob a luz da ciência, para que mais pessoas pudessem conhecer essa experiência e receber este cuidado em saúde como fundamentação para novas práticas.


Subject(s)
Humans , Male , Female , Pregnancy , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Outcome and Process Assessment, Health Care , Complementary Therapeutic Methods , Medicine in the Arts
3.
Nature ; 613(7944): 468-473, 2023 01.
Article in English | MEDLINE | ID: mdl-36653567

ABSTRACT

Producing quantum states at random has become increasingly important in modern quantum science, with applications being both theoretical and practical. In particular, ensembles of such randomly distributed, but pure, quantum states underlie our understanding of complexity in quantum circuits1 and black holes2, and have been used for benchmarking quantum devices3,4 in tests of quantum advantage5,6. However, creating random ensembles has necessitated a high degree of spatio-temporal control7-12 placing such studies out of reach for a wide class of quantum systems. Here we solve this problem by predicting and experimentally observing the emergence of random state ensembles naturally under time-independent Hamiltonian dynamics, which we use to implement an efficient, widely applicable benchmarking protocol. The observed random ensembles emerge from projective measurements and are intimately linked to universal correlations built up between subsystems of a larger quantum system, offering new insights into quantum thermalization13. Predicated on this discovery, we develop a fidelity estimation scheme, which we demonstrate for a Rydberg quantum simulator with up to 25 atoms using fewer than 104 experimental samples. This method has broad applicability, as we demonstrate for Hamiltonian parameter estimation, target-state generation benchmarking, and comparison of analogue and digital quantum devices. Our work has implications for understanding randomness in quantum dynamics14 and enables applications of this concept in a much wider context4,5,9,10,15-20.

4.
Estud. pesqui. psicol. (Impr.) ; 22(3): 1124-1142, set. 2022.
Article in Portuguese | LILACS, Index Psychology - journals | ID: biblio-1428715

ABSTRACT

Investigou-se como a dor e a alegria podem influenciar a construção do ser palhaço(a) com o objetivo de compreender melhor a construção da sua subjetividade. Foram realizadas entrevistas com dez palhaços(as). Utilizou-se como método a análise de conteúdo e o software NVivo® para sistematizar as informações presentes nos discursos dos(as) participantes em doze categorias, agrupadas em dois eixos temáticos e analisadas a partir de sua pertinência na construção do entendimento de ser palhaço(a). Os resultados indicaram que a dor diante de perdas afetivas no processo de ser palhaço(a) passa pela transformação do trágico à comicidade, não para minimizá-la, mas para lidar com a finitude humana por meio da ética, poética e estética de afirmação da vida. A transgressão da palhaçaria permite superar dificuldades e transformá-las criativamente em riso. Conclui-se que o ser palhaço(a) torna-se a vitrine das condições humanas apresentadas por meio do cômico, do trágico, do ridículo, do perder, do político, do rústico e do ser-no-mundo.


It was investigated how pain and joy can influence the construction of being a clown in order to better understand the construction of their subjectivity. Interviews were conducted with ten clowns. Content analysis and the NVivo® software were used as a method to systematize the information present in the participants' speeches into twelve categories, grouped into two thematic axes and analyzed based on its pertinence in the construction of the understanding of being a clown. The results indicated that the pain in the face of affective losses in the process of being a clown goes through the transformation from the tragic to the comic, not to minimize it, but to deal with human finitude through ethics, poetics and life-affirming aesthetics. The transgression of clowning allows you to overcome difficulties and creatively transform them into laughter. It is concluded that being a clown becomes the showcase of human conditions presented through the comic, the tragic, the ridiculous, the losing, the political, the rustic and the being-in-the-world.


Se investigó cómo el dolor y la alegría pueden influir en la construcción del payaso, con el objetivo de comprender mejor la construcción de su subjetividad. Se realizaron entrevistas con diez payasos. El análisis de contenido y el software NVivo® se utilizaron como método para sistematizar la información presente en los discursos de los participantes, en doce categorías, agrupadas en dos ejes temáticos, y analizadas desde la pertinencia en la construcción de la comprensión del payaso. Los resultados indicaron que el dolor ante pérdidas afectivas en el proceso de ser payaso sufre una transformación de lo trágico a lo cómico, no para minimizar el dolor, sino para lidiar con la finitud humana a través de la ética, la poética y la estética afirmadora de la vida. La transgresión del clown te permite superar las dificultades y transformarlas creativamente en risa. Se concluye que ser payaso se convierte en el escaparate de las condiciones humanas que se presentan a través de lo cómico, lo trágico, lo ridículo, lo perdedor, lo político, lo rústico y el ser-en-el-mundo.


Subject(s)
Humans , Male , Female , Pain , Perception , Wit and Humor as Topic , Happiness , Laughter , Qualitative Research
5.
Phys Rev Lett ; 128(11): 110502, 2022 Mar 18.
Article in English | MEDLINE | ID: mdl-35363031

ABSTRACT

Protected qubits such as the 0-π qubit, and bosonic qubits including cat qubits and Gottesman-Kitaev-Preskill (GKP) qubits offer advantages for fault tolerance. Some of these protected qubits (e.g., 0-π qubit and Kerr-cat qubit) are stabilized by Hamiltonians which have (near-)degenerate ground state manifolds with large energy gaps to the excited state manifolds. Without dissipative stabilization mechanisms the performance of such energy-gap-protected qubits can be limited by leakage to excited states. Here, we propose a scheme for dissipatively stabilizing an energy-gap-protected qubit using colored (i.e., frequency-selective) dissipation without inducing errors in the ground state manifold. Concretely we apply our colored dissipation technique to Kerr-cat qubits and propose colored Kerr-cat qubits which are protected by an engineered colored single-photon loss. When applied to the Kerr-cat qubits our scheme significantly suppresses leakage-induced bit-flip errors (which we show are a limiting error mechanism) while only using linear interactions. Beyond the benefits to the Kerr-cat qubit we also show that our frequency-selective loss technique can be applied to a broader class of protected qubits.

6.
Commun Math Phys ; 384(3): 1709-1750, 2021.
Article in English | MEDLINE | ID: mdl-34776522

ABSTRACT

Recent understanding of the thermodynamics of small-scale systems have enabled the characterization of the thermodynamic requirements of implementing quantum processes for fixed input states. Here, we extend these results to construct optimal universal implementations of a given process, that is, implementations that are accurate for any possible input state even after many independent and identically distributed (i.i.d.) repetitions of the process. We find that the optimal work cost rate of such an implementation is given by the thermodynamic capacity of the process, which is a single-letter and additive quantity defined as the maximal difference in relative entropy to the thermal state between the input and the output of the channel. Beyond being a thermodynamic analogue of the reverse Shannon theorem for quantum channels, our results introduce a new notion of quantum typicality and present a thermodynamic application of convex-split methods.

7.
Rev. Bras. Odontol. Leg. RBOL ; 7(2): [2-10], 20200901.
Article in Portuguese | LILACS | ID: biblio-1281443

ABSTRACT

Introdução: A AIDS (Síndrome da Imunodeficiência Adquirida) é a doença causada pela infecção do Vírus da Imunodeficiência Humana (HIV) e é uma infecção sexualmente transmissível. O HIV é um retrovírus, classificado na subfamília dos Lentiviridae. Atualmente, ainda ocorrem casos de discriminação em consultórios odontológicos a pacientes portadores de HIV/AIDS, apesar de todas as informações sobre a doença, na hora do atendimento os profissionais ainda possuem receio e dúvida quanto ao protocolo de atendimento. Objetivo: Avaliar os aspectos éticos do atendimento odontológico de pacientes portadores HIV/AIDS na cidade de Imperatriz-Maranhão, sob a percepção dos mesmos. Material e Método: Foi aplicado um questionário estruturado a 100 pacientes portadores de HIV/AIDS que estavam em tratamento no Centro de Atenção Psicossocial (CAPS) do município de Imperatriz- MA, CAPS III e CAPS AD III, entre os meses de março e abril de 2019. Resultado: Os participantes relataram que sofreram discriminação (41% - 41) em algum momento do atendimento odontológico, 85% (85) dos pacientes não informariam ao cirurgião-dentista que é portador do HIV, sendo o constrangimento (14% - 14) o principal motivo para não informar. Conclusão: O índice de discriminação nos atendimentos odontológicos a pacientes portadores HIV/AIDS no município de Imperatriz-MA é elevado. Há necessidade dos cirurgiões-dentistas buscarem atualizar-se sobre o vírus HIV e a doença AIDS, e sobre aspectos éticos e legais do atendimento a pacientes portadores dessa morbidade, para garantir um atendimento seguro, de qualidade e humanizado.


Subject(s)
Humans , Male , Female , Acquired Immunodeficiency Syndrome , Dentistry , Ethics
8.
Phys Rev Lett ; 124(22): 220601, 2020 Jun 05.
Article in English | MEDLINE | ID: mdl-32567889

ABSTRACT

We prove that the quantum Gibbs states of spin systems above a certain threshold temperature are approximate quantum Markov networks, meaning that the conditional mutual information decays rapidly with distance. We demonstrate the exponential decay for short-ranged interacting systems and power-law decay for long-ranged interacting systems. Consequently, we establish the efficiency of quantum Gibbs sampling algorithms, a strong version of the area law, the quasilocality of effective Hamiltonians on subsystems, a clustering theorem for mutual information, and a polynomial-time algorithm for classical Gibbs state simulations.

9.
Nature ; 574(7779): 505-510, 2019 10.
Article in English | MEDLINE | ID: mdl-31645734

ABSTRACT

The promise of quantum computers is that certain computational tasks might be executed exponentially faster on a quantum processor than on a classical processor1. A fundamental challenge is to build a high-fidelity processor capable of running quantum algorithms in an exponentially large computational space. Here we report the use of a processor with programmable superconducting qubits2-7 to create quantum states on 53 qubits, corresponding to a computational state-space of dimension 253 (about 1016). Measurements from repeated experiments sample the resulting probability distribution, which we verify using classical simulations. Our Sycamore processor takes about 200 seconds to sample one instance of a quantum circuit a million times-our benchmarks currently indicate that the equivalent task for a state-of-the-art classical supercomputer would take approximately 10,000 years. This dramatic increase in speed compared to all known classical algorithms is an experimental realization of quantum supremacy8-14 for this specific computational task, heralding a much-anticipated computing paradigm.

10.
Phys Rev Lett ; 123(11): 110502, 2019 Sep 13.
Article in English | MEDLINE | ID: mdl-31573226

ABSTRACT

Quantum error correction was invented to allow for fault-tolerant quantum computation. Systems with topological order turned out to give a natural physical realization of quantum error correcting codes (QECC) in their ground spaces. More recently, in the context of the anti-de Sitter/conformal field theory correspondence, it has been argued that eigenstates of CFTs with a holographic dual should also form QECCs. These two examples raise the question of how generally eigenstates of many-body models form quantum codes. In this Letter we establish new connections between quantum chaos and translation invariance in many-body spin systems, on one hand, and approximate quantum error correcting codes (AQECC), on the other hand. We first observe that quantum chaotic systems obeying the eigenstate thermalization hypothesis have eigenstates forming approximate quantum error-correcting codes. Then we show that AQECC can be obtained probabilistically from translation-invariant energy eigenstates of every translation-invariant spin chain, including integrable models. Applying this result to 1D classical systems, we describe a method for using local symmetries to construct parent Hamiltonians that embed these codes into the low-energy subspace of gapless 1D quantum spin chains. As explicit examples we obtain local AQECC in the ground space of the 1D ferromagnetic Heisenberg model and the Motzkin spin chain model with periodic boundary conditions, thereby yielding nonstabilizer codes in the ground space and low energy subspace of physically plausible 1D gapless models.

11.
Rev. bras. med. esporte ; 25(5): 379-383, Sept.-Oct. 2019. tab, graf
Article in English | LILACS | ID: biblio-1042353

ABSTRACT

ABSTRACT Introduction Games are recognized tools that can be used for teaching, awareness-building and behavioral change. In the world of competitive sports, it is necessary to both educate athletes and make them aware that doping is an unsportsmanlike practice, particularly because this conduct can be life-threatening. A game called "Heart at Risk" was developed in this context for the purpose of teaching athletes which substances are characterized as doping by the World Antidoping Agency, and to raise their awareness of health hazards through entertainment. Objective Present and empirically evaluate the efficacy of the game as a tool for educating athletes on substances characterized as doping. Methods The sample group was formed by 20 players in the under-20 category of Clube do Remo (Rowing Club), aged over 18 years. The athletes underwent a pre-test, played the Heart at Risk game, and took a post-test at the end. Both tests were related to healthy sport practices (positive factors) and to doping substances (negative factors). Results Regarding the knowledge of positive factors, there was an increase of knowledge in relation to low doses of caffeine (∆ = 40%; p-value= 0.0125) and doping assessment (∆ = 55%; p-value = 0.0017). Regarding negative factors, there was an increase of knowledge in relation to diuretics (∆ = 25%; p-value = 0.0455), contaminated thermogenic (∆ = 35%; p-value = 0.0191), growth hormone-GH (∆ = 50%; p-value = 0.0025), contaminated supplements (∆ = 65%; p-value = 0.0007), and testosterone (∆ = 55%; p-value = 0.0017). Conclusion The Heart at Risk game proved to be an effective resource in the process of learning about prohibited substances and positive factors for sports performance. Level of Evidence IV; Case series.


RESUMO Introdução Jogos são reconhecidos instrumentos que podem ser usados para ensino, conscientização e mudança de comportamentos. No competitivo mundo esportivo, educar e conscientizar que doping é uma prática antiesportiva são duas necesidades, principalmente porque essa atitude pode colocar a vida do atleta em risco. Nesse contexto, foi desenvolvido um jogo, chamado Coração em Jogo, com o objetivo de ensinar aos atletas quais substâncias são caracterizadas como doping pela World Anti-Doping Agency, e ludicamente conscientizá-los dos riscos para a saúde. Objetivo Apresentar e avaliar empiricamente a eficácia do Coração em Jogo como ferramenta para educação de atletas sobre substâncias caracterizadas como doping. Métodos A amostra foi formada por 20 jogadores da categoria sub-20 do Clube do Remo, com idade superior a 18 anos. Os atletas realizaram pré-teste e jogaram o Coração em Jogo, e, ao término, foi aplicado um pós-teste. Ambos os testes eram relativos a práticas esportivas saudáveis (fatores positivos) e sobre substâncias dopantes (fatores negativos). Resultados Em relação ao conhecimento de fatores positivos, houve aumento do conhecimento em baixas doses de cafeína (∆ = 40%; valor de p = 0,0125) e avaliação de dopagem (∆ = 55%; valor de p = 0,0017). Em relação aos fatores negativos, ocorreu aumento do conhecimento em diuréticos (∆ = 25%; valor de p = 0,0455), termogênico contaminado (∆ = 35%; valor de p = 0,0191), hormônio do crescimento (∆ = 50%; valor de p=0,0025), suplementos contaminados (∆ = 65%; valor de p = 0,0007) e testosterona (∆ = 55%; valor de p = 0,0017). Conclusão O Coração em Jogo mostrou-se recurso eficaz na aprendizagem das substâncias proibidas e dos fatores positivos para desempenho do esporte. Nível de Evidência IV; Série de casos.


RESUMEN Introducción Los juegos son reconocidos instrumentos que pueden ser usados para enseñanza, concientización y cambio de comportamientos. En el competitivo mundo deportivo, educar y concientizar que doping es una práctica antideportiva son dos necesidades, principalmente porque esa actitud puede poner la vida del atleta en riesgo. En este contexto se desarrolló un juego llamado "Corazón en juego (Coração em Jogo en su nombre en portugués)", con el objetivo de enseñar a los atletas qué sustancias son caracterizadas como doping por la World Antidoping Agency, y lúdicamente concientizarse de los riesgos para su salud. Objetivo Presentar y evaluar empíricamente la eficacia de "Corazón en Juego", como una herramienta para la educación de atletas sobre sustancias que se caracterizan como doping. Métodos La muestra fue formada por 20 jugadores de la categoría sub-20 del Club del Remo, con edad superior a 18 años. Los atletas realizaron test previo y jugaron "Corazón en Juego", y al término se aplicó un test posterior. Ambos tests se referían a prácticas deportivas saludables (factores positivos) y sobre sustancias dopantes (factores negativos). Resultados Con relación al conocimiento de factores positivos, hubo aumento del conocimiento en bajas dosis de cafeína (Δ = 40%, valor de p = 0,0125) y evaluación de dopaje (Δ = 55%; valor de p = 0,0017). Con relación a los factores negativos, ocurrió aumento del conocimiento en diuréticos (Δ = 25%, valor de p = 0,0455), termogénico contaminado (Δ = 35%, valor de p = 0,0191), hormona del crecimiento (Δ = 50%, valor de p = 0,0025), suplementos contaminados (Δ = 65%, valor de p = 0,0007) y testosterona (Δ = 55%, valor de p = 0,0017). Conclusión "Corazón en Juego", se mostró un recurso eficaz en el aprendizaje de las sustancias prohibidas y de los factores positivos para desempeño del deporte. Nivel de evidencia IV; Serie de casos.

12.
Psychiatr Q ; 90(4): 871-882, 2019 12.
Article in English | MEDLINE | ID: mdl-31501993

ABSTRACT

Different alternative forms of therapy have been studied in relation to their applicability and effectiveness. The use of art therapy in the treatment of depressive disorder is an example frequently employed in several countries. The aim of this research was to identify and discuss which artistic techniques have been applied most frequently in the treatment of depressive disorders and what their main effects are. The research was conducted in the MEDLINE/PubMed, American Psychological Association (APA) and Web of Science databases. The articles were selected through the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA protocol). 14 articles were selected, among which the main techniques of art therapy used were: manual work (drawing, painting, and modeling), music, poetry, photography, theater and contemplation of art pieces. It was found that most of the researches are European and as a field of knowledge they depart mainly from medicine. Of the 14 researches of this review, only two failed in the use of art therapy techniques as a therapeutic tool. It can be understood that art therapy is a safe and reliable tool for treatment not only of depression but also of other mental disorders.


Subject(s)
Art Therapy , Depressive Disorder/therapy , Art Therapy/methods , Art Therapy/statistics & numerical data , Humans
13.
Phys Rev Lett ; 123(1): 010601, 2019 Jul 03.
Article in English | MEDLINE | ID: mdl-31386410

ABSTRACT

Chaotic dynamics in quantum many-body systems scrambles local information so that at late times it can no longer be accessed locally. This is reflected quantitatively in the out-of-time-ordered correlator of local operators, which is expected to decay to 0 with time. However, for systems of finite size, out-of-time-ordered correlators do not decay exactly to 0 and in this paper we show that the residual value can provide useful insights into the chaotic dynamics. When energy is conserved, the late-time saturation value of the out-of-time-ordered correlator of generic traceless local operators scales as an inverse polynomial in the system size. This is in contrast to the inverse exponential scaling expected for chaotic dynamics without energy conservation. We provide both analytical arguments and numerical simulations to support this conclusion.

14.
Phys Rev Lett ; 122(20): 200601, 2019 May 24.
Article in English | MEDLINE | ID: mdl-31172741

ABSTRACT

Thermodynamics imposes restrictions on what state transformations are possible. In the macroscopic limit of asymptotically many independent copies of a state-as for instance in the case of an ideal gas-the possible transformations become reversible and are fully characterized by the free energy. In this Letter, we present a thermodynamic resource theory for quantum processes that also becomes reversible in the macroscopic limit, a property that is especially rare for a resource theory of quantum channels. We identify a unique single-letter and additive quantity, the thermodynamic capacity, that characterizes the "thermodynamic value" of a quantum channel, in the sense that the work required to simulate many repetitions of a quantum process employing many repetitions of another quantum process becomes equal to the difference of the respective thermodynamic capacities. On a technical level, we provide asymptotically optimal constructions of universal implementations of quantum processes. A challenging aspect of this construction is the apparent necessity to coherently combine thermal engines that would run in different thermodynamic regimes depending on the input state. Our results have applications in quantum Shannon theory by providing a generalized notion of quantum typical subspaces and by giving an operational interpretation to the entropy difference of a channel.

15.
Phys Rev Lett ; 123(25): 250601, 2019 Dec 20.
Article in English | MEDLINE | ID: mdl-31922799

ABSTRACT

The resource theory of thermal operations, an established model for small-scale thermodynamics, provides an extension of equilibrium thermodynamics to nonequilibrium situations. On a lattice of any dimension with any translation-invariant local Hamiltonian, we identify a large set of translation-invariant states that can be reversibly converted to and from the thermal state with thermal operations and a small amount of coherence. These are the spatially ergodic states, i.e., states that have sharp statistics for any translation-invariant observable, and mixtures of such states with the same thermodynamic potential. As an intermediate result, we show for a general state that if the gap between the min- and the max-relative entropies to the thermal state is small, then the state can be approximately reversibly converted to and from the thermal state with thermal operations and a small source of coherence. Our proof provides a quantum version of the Shannon-McMillan-Breiman theorem for the relative entropy and a quantum Stein's lemma for ergodic states and local Gibbs states. Our results provide a strong link between the abstract resource theory of thermodynamics and more realistic physical systems as we achieve a robust and operational characterization of the emergence of a thermodynamic potential in translation-invariant lattice systems.

16.
Phys Rev Lett ; 121(4): 040504, 2018 Jul 27.
Article in English | MEDLINE | ID: mdl-30095941

ABSTRACT

Insights from quantum information theory show that correlation measures based on quantum entropy are fundamental tools that reveal the entanglement structure of multipartite states. In that spirit, Groisman, Popescu, and Winter [Phys. Rev. A 72, 032317 (2005)PLRAAN1050-294710.1103/PhysRevA.72.032317] showed that the quantum mutual information I(A;B) quantifies the minimal rate of noise needed to erase the correlations in a bipartite state of quantum systems AB. Here, we investigate correlations in tripartite systems ABE. In particular, we are interested in the minimal rate of noise needed to apply to the systems AE in order to erase the correlations between A and B given the information in system E, in such a way that there is only negligible disturbance on the marginal BE. We present two such models of conditional decoupling, called deconstruction and conditional erasure cost of tripartite states ABE. Our main result is that both are equal to the conditional quantum mutual information I(A;B|E)-establishing it as an operational measure for tripartite quantum correlations.

17.
Phys Rev Lett ; 120(18): 180501, 2018 May 04.
Article in English | MEDLINE | ID: mdl-29775352

ABSTRACT

Three-dimensional (3D) color codes have advantages for fault-tolerant quantum computing, such as protected quantum gates with relatively low overhead and robustness against imperfect measurement of error syndromes. Here we investigate the storage threshold error rates for bit-flip and phase-flip noise in the 3D color code (3DCC) on the body-centered cubic lattice, assuming perfect syndrome measurements. In particular, by exploiting a connection between error correction and statistical mechanics, we estimate the threshold for 1D stringlike and 2D sheetlike logical operators to be p_{3DCC}^{(1)}≃1.9% and p_{3DCC}^{(2)}≃27.6%. We obtain these results by using parallel tempering Monte Carlo simulations to study the disorder-temperature phase diagrams of two new 3D statistical-mechanical models: the four- and six-body random coupling Ising models.

18.
Phys Rev Lett ; 119(5): 050501, 2017 Aug 04.
Article in English | MEDLINE | ID: mdl-28949718

ABSTRACT

We prove that the entanglement entropy of any state evolved under an arbitrary 1/r^{α} long-range-interacting D-dimensional lattice spin Hamiltonian cannot change faster than a rate proportional to the boundary area for any α>D+1. We also prove that for any α>2D+2, the ground state of such a Hamiltonian satisfies the entanglement area law if it can be transformed along a gapped adiabatic path into a ground state known to satisfy the area law. These results significantly generalize their existing counterparts for short-range interacting systems, and are useful for identifying dynamical phase transitions and quantum phase transitions in the presence of long-range interactions.

19.
Acta Cir Bras ; 32(3): 229-235, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28403347

ABSTRACT

PURPOSE:: To evaluate the effects of tramadol hydrochloride associated to remote ischemic perconditioning on oxidative stress. METHODS:: Twenty five male rats (Wistar) underwent right nephrectomy and were distributed into five groups: Sham group (S); Ischemia/Reperfusion group (I/R) with 30 minutes of renal ischemia; Remote ischemic perconditioning group (Per) with three cycles of 10 minutes of I/R performed during kidney ischemia; Tramadol group (T) treated with tramadol hydrochloride (40mg/kg); remote ischemic perconditioning + Tramadol group (Per+T) with both treatments. Oxidative stress was assessed after 24 hours of reperfusion. RESULTS:: Statistical differences were observed in MDA levels between I/R group with all groups (p<0.01), in addition there was difference between Tramadol with Sham, Per and Per+T groups (p<0.05), both in plasma and renal tissue. CONCLUSION:: Remote ischemic perconditioning was more effective reducing renal ischemia-reperfusion injury than administration of tramadol or association of both treatments.


Subject(s)
Ischemia/prevention & control , Ischemic Preconditioning/methods , Kidney/blood supply , Oxidative Stress/drug effects , Protective Agents/pharmacology , Reperfusion Injury/prevention & control , Tramadol/pharmacology , Animals , Combined Modality Therapy/methods , Ischemia/metabolism , Kidney/metabolism , Male , Malondialdehyde/analysis , Oxidative Stress/physiology , Random Allocation , Rats, Wistar , Reperfusion Injury/metabolism , Reproducibility of Results , Time Factors , Treatment Outcome
20.
Phys Rev Lett ; 118(14): 140601, 2017 Apr 07.
Article in English | MEDLINE | ID: mdl-28430500

ABSTRACT

Thermal states are the bedrock of statistical physics. Nevertheless, when and how they actually arise in closed quantum systems is not fully understood. We consider this question for systems with local Hamiltonians on finite quantum lattices. In a first step, we show that states with exponentially decaying correlations equilibrate after a quantum quench. Then, we show that the equilibrium state is locally equivalent to a thermal state, provided that the free energy of the equilibrium state is sufficiently small and the thermal state has exponentially decaying correlations. As an application, we look at a related important question: When are thermal states stable against noise? In other words, if we locally disturb a closed quantum system in a thermal state, will it return to thermal equilibrium? We rigorously show that this occurs when the correlations in the thermal state are exponentially decaying. All our results come with finite-size bounds, which are crucial for the growing field of quantum thermodynamics and other physical applications.

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