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1.
Phys Rev Lett ; 132(21): 213602, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856267

RESUMO

The approach of shortcuts to adiabaticity enables the effective execution of adiabatic dynamics in quantum information processing with enhanced speed. Owing to the inherent trade-off between dynamical speed and the cost associated with the transitionless driving field, executing arbitrarily fast operations becomes impractical. To understand the accurate interplay between speed and energetic cost in this process, we propose theoretically and verify experimentally a new trade-off, which is characterized by a tightly optimized bound within s-parametrized phase spaces. Our experiment is carried out in a single ultracold ^{40}Ca^{+} ion trapped in a harmonic potential. By exactly operating the quantum states of the ion, we execute the Landau-Zener model as an example, where the quantum speed limit as well as the cost are governed by the spectral gap. We witness that our proposed trade-off is indeed tight in scenarios involving both initially eigenstates and initially thermal equilibrium states. Our work helps understanding the fundamental constraints in shortcuts to adiabaticity and illuminates the potential of underutilized phase spaces that have been traditionally overlooked.

2.
Zhonghua Yi Xue Za Zhi ; 104(18): 1617-1622, 2024 May 14.
Artigo em Chinês | MEDLINE | ID: mdl-38742349

RESUMO

Objective: To investigate the inplementation of cardiovascular surgery for congenital heart disease (CHD) in China. Methods: A cross-sectional study was carried out. The CHD cardiovascular surgery data collected by the Chinese Society of Extracorporeal Circulation from 2017 to 2021 in 31 provinces (autonomous regions/municipalities) of China were retrospectively reviewed, the implementation of CHD cardiovascular surgery in different provinces, regions, general/specialized hospitals, and different age groups (whether≤18 years old) were summarized, and the correlation analysis between the number of surgeries carried out in each province/region and the gross regional product and the number of the regional population was performed. Results: Between 2017 and 2021, the annual volume of CHD cardiovascular surgery was 77 120, 77 634, 81 161, 62 663 and 71 492, respectively, showing a decreasing trend. Meanwhile, the proportion of CHD patients aged≤18 years who underwent cardiovascular surgery also showed a downward trend, from 79.8% (61 557/77 120) in 2017 to 58.6% (41 871/71 492) in 2021 (P=0.027). The number of surgical cases varied greatly among different provinces, including 4 provinces with≥5 000 cases and 9 provinces with 2 000-5 000 cases. In the five years, the number of CHD cardiovascular surgeries in Central and East China was the largest, accounting for 41.1%-45.5% of the total surgical cases. The proportion of CHD surgery cases≤18 years old was the highest in Southwest China (69.7%-87.4%) and the lowest in Northeast China (28.2%-68.9%). Except for 2021, the number of cases carried out by each region between 2017 and 2020 was correlated with the gross regional product (r=0.929, 0.929, 0.893 and 0.964, respectively, all P<0.05) and the population (r=0.821, 0.893, 0.821 and 0.857, respectively, all P<0.05). Hospitals that performed more than 100 operations (20.5%±1.2% of the total number of hospitals) completed 86.2%±1.2% of the total number of operations in China during the 5-year period. In 2017 and 2021, the number of CHD cardiovascular surgeries preformed in children's/women's and children's specialized hospitals accounted for 24.3% (18 772/77 120) and 23.8% (17 012/71 492) of the total number of cases in China, respectively. Conclusions: From 2017 to 2021, the number of cardiovascular surgery for CHD decreases slightly, but the proportion of surgery for adult CHD patients increases significantly.There is a strong correlation between the number of CHD operations in each region and their economic development status. The scale of CHD cardiovascular surgery performed in children's hospitals/women's and children's hospitals accounts for about a quarter of the total volume in China.


Assuntos
Cardiopatias Congênitas , Humanos , Cardiopatias Congênitas/cirurgia , China , Inquéritos e Questionários , Procedimentos Cirúrgicos Cardiovasculares/tendências , Adolescente , Criança , Procedimentos Cirúrgicos Cardíacos
3.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(10): 1668-1673, 2020 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-33297624

RESUMO

Objective: To describe the regional and demographic differences on passive non-smokers from 10 regions involved in the China Kadoorie Biobank (CKB) study. Methods: Detailed information regarding passive smoking behaviors related to 317 486 non-smokers who were 30-79 years old from the 10 study regions were gathered and analyzed. Results: Following the standardization of the 2010 China national population, the prevalence rate of passive smoking was 56.7%, and the prevalence rate of living with smokers was 66.5% among the Chinese adults. Both of the aforementioned rates were higher in rural than in urban areas. Meanwhile, the regional distribution of weekly passive smoking frequency and cumulative duration of passive smoking per week and cumulative duration of passive smoking per day were significantly different. The cumulative passive smoking duration per week increased along with the weekly frequency in people living in urban areas. Among women, the weekly passive smoking frequency was the highest, and the cumulative durations per week and per day appeared the lowest in Hunan, opposite to the situation in Henan. The prevalence of passive smoking among participants living with smokers was 2.27 times (95%CI: 2.24-2.29) of those who were not and the association appeared stronger in women (OR=2.61, 95%CI: 2.58-2.64) but not in men (OR=1.01, 95%CI: 0.95-1.06). Almost all the indicators seemed higher in women than those in men, except for the cumulative duration per day. Furthermore, these indicators appeared higher among those who were at younger age or with less education. The prevalence rates of passive smoking and living with smokers were lower but the cumulative duration per day was higher among those with lower household income. And the two rates were higher in married women and lower in married men, as compared to their counterparts. Conclusion: Regional and demographic differences in passive smoking were noticed among study population of CKB in the 10 regions.


Assuntos
Disparidades nos Níveis de Saúde , não Fumantes , Poluição por Fumaça de Tabaco , Adulto , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , não Fumantes/estatística & dados numéricos , Prevalência , Poluição por Fumaça de Tabaco/estatística & dados numéricos
4.
Otolaryngol Head Neck Surg ; 122(3): 334-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10699805

RESUMO

OBJECTIVE: The misdiagnosis and inappropriate treatment of benign positional vertigo have resulted in significant costs to the medical system. In the current medical-economic climate, there is an increased emphasis on cost control. Recent studies have shown that the canalith repositioning procedure (CRP) is effective; the next step is to show the impact of CRP in cost-effective management of benign positional vertigo. METHODS: Forty-six of 100 patients who underwent CRP for benign positional vertigo responded to a survey regarding the financial impact of their disease. They were asked to subjectively estimate the sum of all disease-related expenses. Objective substantiation of this number was estimated by tabulating physician data, laboratory data, and failed treatment costs. RESULTS: The subjective figure totaled $2684.74 per individual. Summation of the tangible objective figures yielded $2009.63 per patient, corroborating the subjective figure. CONCLUSIONS: Because CRP is a relatively simple procedure that can obviate many wasted expenses in most patients, we believe that it is very cost-effective and should be incorporated into routine practice.


Assuntos
Efeitos Psicossociais da Doença , Programas de Assistência Gerenciada/economia , Doença de Meniere/economia , Membrana dos Otólitos , Canais Semicirculares , Análise Custo-Benefício , Diagnóstico Diferencial , Feminino , Humanos , Doença de Meniere/diagnóstico , Doença de Meniere/terapia , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente/economia , Valor Preditivo dos Testes , Procedimentos Desnecessários/economia
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