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1.
Phys Rev Lett ; 133(12): 123202, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39373441

RESUMO

Rydberg alkaline earth atoms are promising tools for quantum simulation and metrology. When one of the two valence electrons is promoted to long-lived circular states, the second valence electron can be optically manipulated without significant autoionization. We harness this feature to demonstrate laser slowing of a thermal atomic beam of circular strontium atoms. By driving the main ion core 422 nm wavelength resonance, we observe a velocity reduction of 50 m/s without significant autoionization. We also show that a superposition of circular states undergoes very weak decoherence during the cooling process, up to the scattering of more than 1000 photons. This robustness opens new perspectives for quantum simulations over long timescales with circular atoms, while simultaneously cooling their motional state. It makes it possible to mitigate the harmful effects of unavoidable heating due to spin-motion coupling during a quantum simulation.

2.
Support Care Cancer ; 32(8): 500, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985388

RESUMO

PURPOSE: Within families affected by parental cancer, open communication impacts the well-being of parents and their children; however, limited research exists on communication patterns in these families. This sub-study addresses this through the Family-SCOUT study, a multicenter, prospective, interventional, and non-randomized investigation with intervention (IG) and control group (CG). The purpose of this sub-study was to identify and compare the differences in communication patterns between the IG and CG as part of the process evaluation. The research question was addressed in both groups: What communication patterns do healthy parents perceive within their families? METHODS: Using a qualitative approach, the study involved interviewing healthy parents as surrogates for their families. The interviews were audio-recorded, transcribed, and coded using a template analysis. The resulting data were analyzed at the group level. RESULTS: Twenty-three interviews were conducted in the IG and 27 interviews in the CG. The analysis of themes centered on communication patterns as seen in the family structure. Both groups exhibited instances of open communication about fears and wishes as well as the use of child-friendly language when discussing cancer. Notable differences were observed: challenges in open communication with children were sorely reported in CG interviews, and "the illness is discussed when necessary" was sorely described in IG interviews. CONCLUSION: This study underscores the need to address and encourage open communication within families with parental cancer.


Assuntos
Comunicação , Neoplasias , Pais , Humanos , Neoplasias/psicologia , Feminino , Masculino , Pais/psicologia , Adulto , Estudos Prospectivos , Criança , Pessoa de Meia-Idade , Pesquisa Qualitativa , Entrevistas como Assunto , Filho de Pais com Deficiência/psicologia
3.
Phys Rev Lett ; 130(2): 023202, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36706390

RESUMO

Circular Rydberg states are excellent tools for quantum technologies, with large mutual interactions and long lifetimes in the tens of milliseconds range, 2 orders of magnitude larger than those of laser-accessible Rydberg states. However, such lifetimes are observed only at zero temperature. At room temperature, blackbody-radiation-induced transfers cancel this essential asset of circular states, which have thus been used mostly so far in specific, complex cryogenic experiments. We demonstrate here, on a laser-cooled atomic sample, a circular state lifetime of more than 1 millisecond at room temperature for a principal quantum number 60. A simple plane-parallel capacitor efficiently inhibits the blackbody-radiation-induced transfers. One of the capacitor electrodes is fully transparent and provides large optical access to the atoms. This result paves the way to a wide range of quantum metrology and quantum simulation room-temperature experiments with long-lived, trapped circular Rydberg atoms in inhibition capacitors with full optical access.

4.
Phys Rev Lett ; 131(9): 093401, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721832

RESUMO

Circular Rydberg atoms (CRAs), i.e., Rydberg atoms with maximal orbital momentum, are highly promising for quantum computation, simulation, and sensing. They combine long natural lifetimes with strong interatomic interactions and coupling to electromagnetic fields. Trapping individual CRAs is essential to harness these unique features. We report the first demonstration of CRAs laser trapping in a programmable array of optical bottle beams. We observe the decay of a trapped rubidium circular level over 5 ms using a novel optical detection method. This first optical detection of alkali CRAs is both spatially and level selective. We finally observe the mechanical oscillations of the CRAs in the traps. This work opens the route to the use of circular levels in quantum devices. It is also promising for quantum simulation and information processing using the full extent of Rydberg manifolds.

5.
Psychiatr Q ; 92(1): 177-191, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32519208

RESUMO

BACKGROUND: This study addresses the question of whether psychosocial functioning measured by the Personal and Social Performance (PSP) Scale is related to various psychopathological measures in a cohort of patients with schizophrenia. METHODS: The 'Neuroleptic Strategy Study' (NeSSy) performed at 14 German hospitals between 2010 and 2013 compared two treatment strategies instead of individual drugs. Secondary end-points were the two PSP scales as well as measures of quality of life (SF-36) and the Positive and Negative Syndrome Scale (PANSS). RESULTS: 149 patients were randomised. There was no difference between the two treatment strategies (first-generation versus second-generation antipsychotics) with regard to the PSP. There were differences in doctors' assessments regarding psychosocial functioning compared with patients' own assessments. Furthermore, there were relationships between the PSP and quality of life, level of skills (ICF), and severity of disease (PANSS), level of sexual activities and poor well-being under antipsychotic medication but not with cognitive changes. CONCLUSIONS: The findings on psychosocial functioning of patients with schizophrenia related to severity and skill level could be confirmed. Further findings were the correlation between psychosocial functioning and quality of life, well-being under treatment, and sexuality what emphasizes the substantial importance of a reduced psychosocial functioning.


Assuntos
Antipsicóticos/uso terapêutico , Funcionamento Psicossocial , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Qualidade de Vida
6.
Phys Rev Lett ; 125(26): 263001, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449789

RESUMO

Alkaline earth Rydberg atoms are very promising tools for quantum technologies. Their highly excited outer electron provides them with the remarkable properties of Rydberg atoms and, notably, with a huge coupling to external fields or to other Rydberg atoms while the ionic core retains an optically active electron. However, low angular-momentum Rydberg states suffer almost immediate autoionization when the core is excited. Here, we demonstrate that strontium circular Rydberg atoms with a core excited in a 4D metastable level are impervious to autoionization over more than a few millisecond time scale. This makes it possible to trap and laser-cool Rydberg atoms. Moreover, we observe singlet to triplet transitions due to the core optical manipulations, opening the way to a microwave to optical quantum interface.

7.
Phys Rev Lett ; 124(12): 123201, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32281867

RESUMO

Rydberg atoms are remarkable tools for quantum simulation and computation. They are the focus of an intense experimental activity, mainly based on low-angular-momentum Rydberg states. Unfortunately, atomic motion and levels lifetime limit the experimental timescale to about 100 µs. Here, we demonstrate two-dimensional laser trapping of long-lived circular Rydberg states for up to 10 ms. Our method is very general and opens many opportunities for quantum technologies with Rydberg atoms. The 10 ms trapping time corresponds to thousands of interaction cycles in a circular-state-based quantum simulator. It is also promising for quantum metrology and quantum information with Rydberg atoms, by bringing atom-field interaction times into unprecedented regimes.

8.
Phys Rev Lett ; 123(6): 060404, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31491182

RESUMO

The efficient quantum state reconstruction algorithm described by Six et al. [Phys. Rev. A 93, 012109 (2016)PLRAAN2469-992610.1103/PhysRevA.93.012109] is experimentally implemented on the nonlocal state of two microwave cavities entangled by a circular Rydberg atom. We use information provided by long sequences of measurements performed by resonant and dispersive probe atoms over timescales involving the system decoherence. Moreover, we benefit from the consolidation, in the same reconstruction, of different measurement protocols providing complementary information. Finally, we obtain realistic error bars for the matrix elements of the reconstructed density operator. These results demonstrate the pertinence and precision of the method, directly applicable to any complex quantum system.

9.
Phys Rev Lett ; 123(14): 143605, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31702170

RESUMO

The simple resonant Rabi oscillation of a two-level system in a single-mode coherent field reveals complex features at the mesoscopic scale, with oscillation collapses and revivals. Using slow circular Rydberg atoms interacting with a superconducting microwave cavity, we explore this phenomenon in an unprecedented range of interaction times and photon numbers. We demonstrate the efficient production of cat states, which are the quantum superposition of coherent components with nearly opposite phases and sizes in the range of few tens of photons. We measure cuts of their Wigner functions revealing their quantum coherence and observe their fast decoherence. This experiment opens promising perspectives for the rapid generation and manipulation of nonclassical states in cavity and circuit quantum electrodynamics.

10.
Am J Transplant ; 17(7): 1802-1812, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28117941

RESUMO

Heart transplantation is the therapy of choice for end-stage heart failure. However, hemodynamic instability, which has been demonstrated in brain-dead donors (BDD), could also affect the posttransplant graft function. We tested the hypothesis that treatment of the BDD with the dopamine derivate n-octanoyl-dopamine (NOD) improves donor cardiac and graft function after transplantation. Donor rats were given a continuous intravenous infusion of either NOD (0.882 mg/kg/h, BDD+NOD, n = 6) or a physiological saline vehicle (BDD, n = 9) for 5 h after the induction of brain death by inflation of a subdural balloon catheter. Controls were sham-operated (n = 9). In BDD, decreased left-ventricular contractility (ejection fraction; maximum rate of rise of left-ventricular pressure; preload recruitable stroke work), relaxation (maximum rate of fall of left-ventricular pressure; Tau), and increased end-diastolic stiffness were significantly improved after the NOD treatment. Following the transplantation, the NOD-treatment of BDD improved impaired systolic function and ventricular relaxation. Additionally, after transplantation increased interleukin-6, tumor necrosis factor TNF-α, NF-kappaB-p65, and nuclear factor (NF)-kappaB-p105 gene expression, and increased caspase-3, TNF-α and NF-kappaB protein expression could be significantly downregulated by the NOD treatment compared to BDD. BDD postconditioning with NOD through downregulation of the pro-apoptotic factor caspase-3, pro-inflammatory cytokines, and NF-kappaB may protect the heart against the myocardial injuries associated with brain death and ischemia/reperfusion.


Assuntos
Morte Encefálica , Dopamina/análogos & derivados , Transplante de Coração/métodos , Precondicionamento Isquêmico , Traumatismo por Reperfusão/prevenção & controle , Doadores de Tecidos , Função Ventricular Esquerda/fisiologia , Animais , Caspase 3/metabolismo , Dopamina/farmacologia , Interleucina-6/metabolismo , Masculino , NF-kappa B/metabolismo , Ratos , Ratos Endogâmicos Lew , Fator de Necrose Tumoral alfa/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos
11.
Phys Rev Lett ; 118(25): 253603, 2017 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28696734

RESUMO

We realize a coherent transfer between a laser-accessible low-angular-momentum Rydberg state and the circular Rydberg level with maximal angular momentum. It is induced by a radio frequency field with a high-purity σ^{+} polarization resonant on Stark transitions inside the hydrogenic Rydberg manifold. We observe over a few microseconds more than 20 coherent Rabi oscillations between the initial Rydberg state and the circular level. We characterize these many-Rydberg-level oscillations and find them in perfect agreement with a simple model. This coherent transfer opens the way to hybrid quantum gates bridging the gap between optical communication and quantum information manipulations with microwave cavity and circuit quantum electrodynamics.

13.
Nervenarzt ; 88(5): 510-519, 2017 May.
Artigo em Alemão | MEDLINE | ID: mdl-27491537

RESUMO

BACKGROUND: The proliferation of biological psychiatry has greatly increased over the last two decades. With the possibility to carry out brain research using modern technical methods, it seemed that social influencing factors would lose importance in the development of mental diseases; however, in actual fact this does not seem to be justified. It is necessary to overcome this separation, in that social factors are incorporated into a conceptual framework in the development of mental diseases, which simultaneously also takes the results of current neurobiological research into consideration. OBJECTIVES AND METHODS: The aims of this review article are to summarize the current state of sociopsychiatric research and to emphasize the perspectives of the biological principles and their validity with respect to the social dimensions of psychiatry, as exemplified by schizophrenic disorders. The article presents the options for a biosocial approach in social psychiatry and gives an overview of the currently available literature. RESULTS AND CONCLUSION: There is an abundance of neurobiological research approaches, which are closely associated with sociopsychiatric topics, such as social cognition. Social psychiatry and biological psychiatry should no longer be considered as diametrically opposed subdisciplines. On the contrary, the options which could emerge from a synthesis must be used in research and clinical practice.


Assuntos
Encéfalo/fisiopatologia , Psiquiatria Comunitária/organização & administração , Pesquisa Interdisciplinar/organização & administração , Modelos Organizacionais , Neurobiologia/organização & administração , Psiquiatria/organização & administração , Esquizofrenia/fisiopatologia , Atenção à Saúde/organização & administração , Alemanha , Humanos , Equipe de Assistência ao Paciente/organização & administração , Esquizofrenia/diagnóstico , Esquizofrenia/terapia
14.
Phys Rev Lett ; 115(1): 013001, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26182093

RESUMO

We show that microwave spectroscopy of a dense Rydberg gas trapped on a superconducting atom chip in the dipole blockade regime reveals directly the dipole-dipole many-body interaction energy spectrum. We use this method to investigate the expansion of the Rydberg cloud under the effect of repulsive van der Waals forces and the breakdown of the frozen gas approximation. This study opens a promising route for quantum simulation of many-body systems and quantum information transport in chains of strongly interacting Rydberg atoms.

15.
Transpl Infect Dis ; 17(3): 371-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25817044

RESUMO

BACKGROUND: Influenza vaccination is generally recommended to hematopoietic stem cell transplant (HSCT) recipients. However, the seasonal subunit vaccination response is frequently suboptimal, and alternate more efficient vaccination systems must be examined. We compared the immunogenicity of an adjuvanted virosomal influenza and subunit vaccine in HSCT recipients. METHODS: The immunogenicity after a single dose (0.5 mL) of adjuvanted trivalent virosomal vaccination was evaluated in a study cohort of 21 HSCT recipients and compared to a control cohort of 30 HSCT recipients who received a single dose (0.5 mL) of non-adjuvanted seasonal trivalent subunit vaccination over 4 seasons from 2010 to 2014. Whole blood interferon-gamma (IFN-γ) release assays were tested, both before and 30 days after vaccination, in response to influenza pandemic (pdm) H1N1, H3N2, and B antigens. HLA-A*02 dextramers, to gauge for the absolute number of antigen-specific CD8(+) T-cells, and pdm 2009 hemagglutinin inhibition (HI) assays, to test for neutralizing antibodies, were used as immunological readouts. RESULTS: The pdm HI titers were poor in both cohorts with only 23% (5/21) after virosomal vaccination and 13.3% (4/30) in the seasonal vaccine cohort having protective titers (≥40). The delta change of IFN-γ production in response to influenza pdm H1N1 (P = 0.005) and influenza B antigens (P = 0.01) were significantly elevated in blood from individuals who received the virosomal as compared to the seasonal vaccine. The IFN-γ response to pdm H1N1 was stronger (P < 0.001), as compared to seasonal vaccination, in patients vaccinated >6 month post HSCT. We detected a significant increase in the frequency of matrix 1 (GILGFVTL) dextramer-specific CD8(+) T-cells after the virosomal vaccine (P = 0.01). No differences were seen in the hemagglutinin-specific CD8(+) T-cells between the 2 cohorts. CONCLUSION: Vaccination using a virosomal delivery system is beneficial in eliciting robust cellular immune responses to pdm H1N1 influenza in SCT recipients.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Transplante de Células-Tronco/efeitos adversos , Vacinação , Adjuvantes Farmacêuticos , Adulto , Idoso , Linfócitos T CD8-Positivos/imunologia , Estudos de Coortes , Feminino , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Influenza Humana/virologia , Interferon gama/imunologia , Masculino , Pessoa de Meia-Idade , Estações do Ano , Suécia , Transplante Homólogo/efeitos adversos , Adulto Jovem
16.
Eur Arch Psychiatry Clin Neurosci ; 263(8): 655-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23494332

RESUMO

A core feature of schizophrenia is the breakdown of the sense of self. A widespread clinical consequence of impaired self-awareness is a lack of insight. Self-face recognition is regarded as one aspect of self-awareness; how this relates to other self-referential processes such as insight into the disorder is as yet unknown. Nineteen patients with schizophrenia performed a facial recognition task using video morphings during which an average face gradually transformed into one's own, a famous or an unfamiliar face (and vice versa). Reaction times to detect faces during the transitions were compared between patients and a matched control group. In the patient group, we also examined correlations between face recognition and insight, psychopathology, and self-evaluation. Both patients with schizophrenia and controls recognised their own faces faster than unfamiliar faces. Whereas healthy subjects recognised a famous face at an intermediate speed that did not differ significantly from the recognition of one's own and unfamiliar faces, schizophrenia patients recognised the famous face, similar to their own face, significantly faster than an unfamiliar face. Moreover, in the patient group, higher insight correlated with faster reaction times in distinguishing one's own from famous faces. Patients with schizophrenia seem to distinguish less than controls between their own and a famous face relative to an unfamiliar face. Patients with good insight into the disorder, however, were better able to differentiate between their own and a famous face. This study supports the view that self-face recognition is an indicator for higher-order self-awareness.


Assuntos
Face , Reconhecimento Visual de Modelos/fisiologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Autoimagem , Adulto , Análise de Variância , Feminino , Humanos , Modelos Lineares , Masculino , Estimulação Luminosa , Escalas de Graduação Psiquiátrica , Tempo de Reação
17.
Phys Rev Lett ; 108(24): 243602, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23004271

RESUMO

Fock states with photon numbers n up to 7 are prepared on demand in a microwave superconducting cavity by a quantum feedback procedure that reverses decoherence-induced quantum jumps. Circular Rydberg atoms are used as quantum nondemolition sensors or as single-photon emitter or absorber actuators. The quantum nature of these actuators matches the correction of single-photon quantum jumps due to relaxation. The flexibility of this method is suited to the generation of arbitrary sequences of Fock states.

18.
Phys Rev Lett ; 107(1): 010402, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21797525

RESUMO

We propose an engineered reservoir inducing the relaxation of a cavity field towards nonclassical states. It is made up of two-level atoms crossing the cavity one at a time. Each atom-cavity interaction is first dispersive, then resonant, then dispersive again. The reservoir pointer states are those produced by an effective Kerr Hamiltonian acting on a coherent field. We thereby stabilize squeezed states and quantum superpositions of multiple coherent components in a cavity having a finite damping time. This robust decoherence protection method could be implemented in state-of-the-art experiments.

19.
Phys Rev Lett ; 105(21): 213601, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21231304

RESUMO

We discuss an implementation of quantum Zeno dynamics in a cavity quantum electrodynamics experiment. By performing repeated unitary operations on atoms coupled to the field, we restrict the field evolution in chosen subspaces of the total Hilbert space. This procedure leads to promising methods for tailoring nonclassical states. We propose to realize "tweezers" picking a coherent field at a point in phase space and moving it towards an arbitrary final position without affecting other nonoverlapping coherent components. These effects could be observed with a state-of-the-art apparatus.

20.
Eur J Med Res ; 15(9): 403-9, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20952350

RESUMO

OBJECTIVE: given sparse research on the issue, this study sought to shed light upon the interactions of alexithymia, emotion processing, and social anxiety in adults with attention-deficit hyperactivity disorder (ADHD). SUBJECTS AND METHODS: 73 German adults with ADHD according to DSM-IV diagnostic criteria participated. We used the Toronto Alexithymia Scale (TAS-20) to assess alexithymia, the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS) to assess different features of social anxiety, and we applied the German "Experience of Emotions Scalerdquor; (SEE) to measure emotion processing. RESULTS: 40% of the sample were found to meet the DSM-IV criteria of social anxiety disorder, and about 22% were highly alexithymic according to a TAS-20 total score ≥ 61; however, the mean TAS-20 total score of 50.94 ± 9.3 was not much higher than in community samples. Alexithymic traits emerged to be closely linked to emotion processing problems, particularly 'difficulty accepting own emotions', and to social anxiety features. DISCUSSION/CONCLUSION: our findings suggest interactions of alexithymia, emotion processing dysfunction, and social anxiety in adults with ADHD, which may entail the therapeutic implication to thoroughly instruct these patients to identify, accept, communicate, and regulate their emotions to aid reducing interaction anxiety.


Assuntos
Sintomas Afetivos/epidemiologia , Transtornos de Ansiedade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Emoções/fisiologia , Transtornos Fóbicos/epidemiologia , Adulto , Sintomas Afetivos/psicologia , Transtornos de Ansiedade/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Comorbidade , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/estatística & dados numéricos , Transtornos Fóbicos/psicologia , Prevalência , Distribuição por Sexo , Comportamento Social
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