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1.
Phys Rev Lett ; 129(5): 056801, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35960588

RESUMO

Intermediate-scale quantum technologies provide new opportunities for scientific discovery, yet they also pose the challenge of identifying suitable problems that can take advantage of such devices in spite of their present-day limitations. In solid-state materials, fractional quantum Hall phases continue to attract attention as hosts of emergent geometrical excitations analogous to gravitons, resulting from the nonperturbative interactions between the electrons. However, the direct observation of such excitations remains a challenge. Here, we identify a quasi-one-dimensional model that captures the geometric properties and graviton dynamics of fractional quantum Hall states. We then simulate geometric quench and the subsequent graviton dynamics on the IBM quantum computer using an optimally compiled Trotter circuit with bespoke error mitigation. Moreover, we develop an efficient, optimal-control-based variational quantum algorithm that can efficiently simulate graviton dynamics in larger systems. Our results open a new avenue for studying the emergence of gravitons in a new class of tractable models on the existing quantum hardware.

2.
Med Int (Lond) ; 4(4): 35, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756457

RESUMO

Posterior fixation of the subaxial cervical spine (SCS) commonly relies on the application of lateral mass screws (LMS), with pedicle screws being a less prevalent alternative. The present study provides another option: A recently introduced novel approach, the Attallah screw, intended to ensure a safety profile comparable to that of LMS, combined with a strength profile similar to that of pedicle screws. The focus of the present study is the comparative analysis of peak insertion torques for these three screw types. Employing standard surgical techniques and instruments, Attallah screws were scheduled for insertion on the right side of the SCS in 15 cadavers, pedicle screws on the left side in 8 cadavers, and LMS on the left side in the remaining 7 cadavers. The peak insertion torque was recorded using an electronic torque screwdriver. The results revealed that the peak insertion torques were similar in the pedicle and the Attallah screw at C3, C4 and C7, but differed at C5 (mean ± SD; pedicle, 79.5±19.6 cNm; Attallah, 56.7±18.5 cNm; P=0.029) and C6 (pedicle, 85.4±28.7 cNm; Attallah, 49.8±17.9 cNm; P=0.004) in favor of the superior pedicle screw measurements. The peak insertion torques of the pedicle screw were superior to the corresponding data from the LMS from C4 to C7. By contrast, the peak insertion torques of the Attallah screw were only superior to those of the LMS at C7 (Attallah, 69.5±24.5 cNm; lateral mass, 40.5±21.4 cNm; P=0.030), although similar trends were observed at the other cervical levels. On the whole, the findings presented herein indicate the level-dependent superior robustness of the Attallah screw as a posterior cervical fixation method compared to the LMS. However, from a biomechanical perspective, the pedicle screw remains the preeminent choice for fixation within the C5-C6 range.

3.
J Egypt Soc Parasitol ; 34(1 Suppl): 417-28, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15124750

RESUMO

Hepatitis C virus (HCV) is a major cause of morbidity worldwide. The aim of this study is to evaluate hematological manifestations occurring in patients suffering from chronic HCV infection. Positive HCV-RNA cases (109) were subjected to the following C.B.C., P.T., P.T.T., B.T., C.T., detection of F.D.Ps., measurement of plasma AAT then B.M. aspiration and examination for 20 cases of them. Patients were classified into 3 groups according to the histopathological staging and grading of liver biopsy. Comparison between groups according to histopathological grading and staging for hematological and chemical parameters revealed significant statistical difference in platelets count, S. Albumin, ALT and AST levels. Comparison between groups according to histopathological grading and staging for coagulation profile, AAT level and FDPs revealed significant statistical difference regarding all parameters. Bone marrow aspiration and examination revealed mild hypocellularity with increased number of lymphocytes and relevance of plasmacytoid-lymphocytes. From this study we can conclude that patients with chronic HCV infection are in need for good observation and follow up before taking therapy because they have some hematological abnormalities which need more concern in order to decrease their progressive effect before starting therapy for HCV per se. They should be always screened and given liver and marrow supportive supplements.


Assuntos
Hepatite C Crônica/sangue , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biópsia , Testes de Coagulação Sanguínea , Contagem de Eritrócitos , Hepatite C Crônica/enzimologia , Humanos , Fígado/enzimologia , Fígado/patologia , Fígado/virologia , Contagem de Plaquetas , Albumina Sérica/análise
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