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1.
Phys Rev Lett ; 128(5): 050602, 2022 Feb 04.
Article in English | MEDLINE | ID: mdl-35179942

ABSTRACT

Repeated local measurements of quantum many-body systems can induce a phase transition in their entanglement structure. These measurement-induced phase transitions (MIPTs) have been studied for various types of dynamics, yet most cases yield quantitatively similar critical exponents, making it unclear how many distinct universality classes are present. Here, we probe the properties of the conformal field theories governing these MIPTs using a numerical transfer-matrix method, which allows us to extract the effective central charge, as well as the first few low-lying scaling dimensions of operators at these critical points for (1+1)-dimensional systems. Our results provide convincing evidence that the generic and Clifford MIPTs for qubits lie in different universality classes and that both are distinct from the percolation transition for qudits in the limit of large on-site Hilbert space dimension. For the generic case, we find strong evidence of multifractal scaling of correlation functions at the critical point, reflected in a continuous spectrum of scaling dimensions.

2.
J Fr Ophtalmol ; 43(9): 858-861, 2020 Nov.
Article in French | MEDLINE | ID: mdl-32807545

ABSTRACT

We report herein the first French case of Saturday Night Retinopathy. A 39-year-old man presented to the emergency room with unilateral vision loss in the left eye with redness but no pain. Visual acuity OS was "light perception" and OD 20/20. The left eye was hyperemic with a fixed, dilated pupil; fundus examination revealed a macular cherry-red spot within a pale, ischemic retina. The patient was admitted to a stroke centre. The neurological work-up and head CT were normal. He also underwent evaluation for possible carotid or cardiac etiologies, all of which were negative. Current smoking was the only cardiovascular risk factor found. The patient reportedly fell asleep face down at his kitchen table after consuming a large amount of alcohol, with his left eye pressed into his arm throughout the night. Six similar cases have been reported in the literature since 1973. The prognosis for vision is dismal. Only public awareness and prevention might avoid this serious functional disability.


Subject(s)
Retinal Artery Occlusion , Retinal Diseases , Adult , Fundus Oculi , Humans , Male , Retina , Retinal Diseases/diagnosis , Retinal Diseases/etiology , Visual Acuity
3.
Rev Neurol (Paris) ; 176(6): 439-443, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32418701

ABSTRACT

Older adults with epilepsy frequently report changes in memory function, with a concern about degenerative disease. However, the precise limit between memory changes related to the effects of longstanding chronic epilepsy and physiological aging on memory abilities is very difficult to specify. Knowledge about characteristics of physiological cognitive aging, its influence on memory test results, and its interactions with clinical variables related to epileptic disease are therefore essential to interpret memory scores. This paper aims at presenting an overview of the different factors that might modulate the developmental trajectory of episodic memory in chronic temporal lobe epilepsy. For this purpose, the effects of age on memory in healthy and epileptic persons will be first reviewed with a special focus on episodic memory functions in chronic temporal lobe epilepsy. Finally, scientific evidence supporting or not the presence of an accelerated memory decline in patients with longstanding epilepsy will be presented by discussing the interests and the limits of the existing literature. Identifying the best outcome measures to assess episodic memory and understanding the risk factors that might precipitate memory decline are key knowledge to improve the clinical care and quality of life of persons with chronic temporal lobe epilepsy.


Subject(s)
Aging/physiology , Epilepsy, Temporal Lobe/epidemiology , Epilepsy, Temporal Lobe/psychology , Age Factors , Aging/psychology , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/epidemiology , Cognitive Dysfunction/etiology , Epilepsy, Temporal Lobe/diagnosis , Humans , Memory/physiology , Memory Disorders/diagnosis , Memory Disorders/epidemiology , Memory Disorders/etiology , Neuropsychological Tests
4.
Phys Rev Lett ; 114(21): 217201, 2015 May 29.
Article in English | MEDLINE | ID: mdl-26066454

ABSTRACT

We study the infinite-temperature properties of an infinite sequence of random quantum spin chains using a real-space renormalization group approach, and demonstrate that they exhibit nonergodic behavior at strong disorder. The analysis is conveniently implemented in terms of SU(2)_{k} anyon chains that include the Ising and Potts chains as notable examples. Highly excited eigenstates of these systems exhibit properties usually associated with quantum critical ground states, leading us to dub them "quantum critical glasses." We argue that random-bond Heisenberg chains self-thermalize and that the excited-state entanglement crosses over from volume-law to logarithmic scaling at a length scale that diverges in the Heisenberg limit k→∞. The excited state fixed points are generically distinct from their ground state counterparts, and represent novel nonequilibrium critical phases of matter.

6.
Ann Readapt Med Phys ; 48(3): 111-7, 2005 Apr.
Article in French | MEDLINE | ID: mdl-15833258

ABSTRACT

OBJECTIVE: To test the possible link between first investigation and development of spastic diplegia. METHOD: A long-term retrospective study was carried out in the Neonatal Medicine Department of Arras Hospital, the C.A.M.S.P. of that town and with corresponding therapists. RESULTS: The study undertaken from January 1, 1991, to December 31, 1997, involved 56 children suspected of developing spastic diplegia and requiring a specialized course of treatment during the evolution of disease. In 32, evolution of disease was favourable, and in 24 spastic diplegia developed. An unfavourable evolution was significantly associated with late intervention of rehabilitation. CONCLUSION: Although few pre- or neonatal factors differentiated the two groups of children in their opposite evolution, haemorrhage during pregnancy and early detection seem to be determining factors in spastic diplegia.


Subject(s)
Cerebral Palsy/diagnosis , Cerebral Palsy/rehabilitation , Early Diagnosis , Humans , Infant , Prognosis , Retrospective Studies , Risk
7.
J Fr Ophtalmol ; 19(12): 743-7, 1996.
Article in French | MEDLINE | ID: mdl-9033898

ABSTRACT

PURPOSE: Epinephrine may be used for ocular irrigation during ophthalmic surgery when diluted in balanced saline solutions. In aqueous solution, epinephrine breakdown depends on pH, light, temperature, oxidating agents and increases with time. METHODS: The stability of epinephrine in plastic bags prepared in low concentrations (1 mg/L) was studied by HPLC analysis with UV detection, completed with pH determinations, performed after storage (protected from light) in various conditions: at room temperature (+25 degrees C), at +4 degrees C (in a refrigerator), at -20 degrees C (in a freezer). Spontaneous defreezing at room temperature was compared to accelerated thawing in a microwave oven. RESULTS: Epinephrine diluted in ocular irrigation solutions (1 mg/L) was stable for 2 days at room temperature, 14 days at +4 degrees C and 35 days at -20 degrees C. Microwave thawing did not alter the stability of epinephrine. CONCLUSION: The preparation of epinephrine solutions for intra-ocular irrigation may be centralized if the bags are stored less than two weeks in a refrigerator and less than one month in a freezer.


Subject(s)
Epinephrine , Mydriatics , Vasoconstrictor Agents , Drug Stability , Humans , Ophthalmic Solutions , Preservatives, Pharmaceutical , Temperature , Therapeutic Irrigation , Time Factors
8.
J Homosex ; 25(4): 31-45, 1993.
Article in English | MEDLINE | ID: mdl-8106739

ABSTRACT

The impact of previous interpersonal contact or exposure to male homosexuals and lesbians on interviewing strategy was assessed. Previous research on attitudes toward homosexuals suggests that prior exposure reduces the negativity of attitudes toward homosexuals. In support of that research and research looking at the use of confirmatory questioning strategies in social interactions, it was expected that individuals with prior exposure to homosexuals and/or positive attitudes toward homosexuals would choose fewer negative information-seeking questions for a proposed interview. The results support previous research findings regarding attitudes towards gay men and lesbians and suggest that pre-interview attitudes and prior exposure may influence interviewer strategy.


Subject(s)
Attitude , Homosexuality/psychology , Interpersonal Relations , Personnel Selection , Adult , Female , Humans , Male , Prejudice
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