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1.
Phys Rev Lett ; 132(4): 040602, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335353

RESUMO

We demonstrate a novel experimental tool set that enables irreversible multiqubit operations on a quantum platform. To exemplify our approach, we realize two elementary nonunitary operations: the or and nor gates. The electronic states of two trapped ^{40}Ca^{+} ions encode the logical information, and a cotrapped ^{88}Sr^{+} ion provides the irreversibility of the gate by a dissipation channel through sideband cooling. We measure 87% and 81% success rates for the or and nor gates, respectively. The presented methods are a stepping stone toward other nonunitary operations such as in quantum error correction and quantum machine learning.

2.
Neth Heart J ; 28(5): 280-292, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32189208

RESUMO

Guidelines suggest using frailty characteristics in the work-up for a transcatheter aortic valve implantation (TAVI). There are many frailty-screening tools with different components. The prognostic value of the individual parameters in frailty is as yet unclear. The objective of this systematic review and meta-analysis was to find and pool predictors for 1­year mortality after TAVI. We followed a two-step approach. First, we searched for randomised controlled trials on TAVI to identify frailty parameters used in these studies. Second, we searched for publications on these frailty parameters. Articles were included for pooled analysis if the studied frailty parameters were dichotomised with clear cut-off values based on common standards or clinical practice and reported adjusted hazard ratios (HR) of 1­year mortality after TAVI. We calculated pooled effect estimates of 49 studies based on dichotomised frailty scores (HR: 2.16, 95% CI: 1.57-3.00), chronic lung disease (HR: 1.57, 95% CI: 1.45-1.70), estimated glomerular filtration rate <30 ml/min (HR: 1.95, 95% CI: 1.68-2.29), body mass index <20 kg/m2 (HR: 1.49, 95% CI: 1.09-2.03), hypoalbuminaemia (HR: 1.77, 95% CI: 1.38-2.25), anaemia (HR: 2.08, 95% CI: 0.93-4.66), low gait speed (HR: 13.33, 95% CI: 1.75-101.49) and Katz activities of daily living (ADL) score of 1 or more deficits (HR: 5.16, 95% CI: 0.77-34.47). Chronic lung disease, chronic kidney disease, underweight, hypoalbuminaemia, a low frailty score, anaemia, low gait speed and an ADL deficiency were associated with worse 1­year outcomes after TAVI.

3.
Neth Heart J ; 28(10): 520-525, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32333256

RESUMO

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is increasingly being used as an alternative to conventional surgical valve replacement. Prosthetic valve endocarditis (PVE) is a rare but feared complication after TAVR, with reported first-year incidences varying from 0.57 to 3.1%. This study was performed to gain insight into the incidence and outcome of PVE after TAVR in the Netherlands. METHODS: A multicentre retrospective registry study was performed. All patients who underwent TAVR in the period 2010-2017 were screened for the diagnosis of infective endocarditis in the insurance database and checked for the presence of PVE before analysis of general characteristics, PVE parameters and outcome. RESULTS: A total of 3968 patients who underwent TAVR were screened for PVE. During a median follow-up of 33.5 months (interquartile range (IQR) 22.8-45.8), 16 patients suffered from PVE (0.4%), with a median time to onset of 177 days (IQR 67.8-721.3). First-year incidence was 0.24%, and the overall incidence rate was 0.14 events per 1000 person-years. Overall mortality during follow-up in our study was 31%, of which 25% occurred in hospital. All patients were treated conservatively with intravenous antibiotics alone, and none underwent a re-intervention. Other complications of PVE occurred in 5 patients (31%) and included aortic abscess (2), decompensated heart failure (2) and cerebral embolisation (1). CONCLUSION: PVE in patients receiving TAVR is a relatively rare complication and has a high mortality rate.

4.
Neth Heart J ; 28(5): 240-248, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32112292

RESUMO

BACKGROUND: Immobilisation of patients after transfemoral transcatheter aortic valve implantation (TF-TAVI) is the standard of care, mostly to prevent vascular complications. However, immobilisation may increase post-operative complications such as delirium and infections. In this trial, we determine whether it is feasible and safe to implement early ambulation after TF-TAVI. METHODS: We prospectively included TF-TAVI patients from 2016 to 2018. Patients were assessed for eligibility using our strict safety protocol and were allocated (based on the time at which the procedure ended) to the EARLY or REGULAR group. RESULTS: A total of 150 patients (49%) were deemed eligible for early mobilisation, of which 73 were allocated to the EARLY group and 77 to the REGULAR group. The overall population had a mean age of 80 years, 48% were male with a Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score of 3.8 ± 1.8. Time to mobilisation was 4 h 49 min ± 31 min in the EARLY group versus 20 h 7 min ± 3 h 6 min in the REGULAR group (p < 0.0001). There were no differences regarding the primary endpoint. No major vascular complications occurred and a similar incidence of minor vascular complications was seen in both groups (4/73 [5.5%] vs 6/77 [7.8%], p = 0.570). The incidence of the combined secondary endpoint was lower in the EARLY group (p = 0.034), with a numerically lower incidence for all individual outcomes (delirium, infections, pain and unplanned urinary catheter use). CONCLUSION: Early mobilisation (ambulation 4-6 h post-procedure) of TF-TAVI patients is feasible and safe. Early ambulation decreases the combined incidence of delirium, infections, pain and unplanned urinary catheter use, and its adoption into contemporary TAVI practice may therefore be beneficial.

5.
Neth Heart J ; 27(9): 443-450, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31111457

RESUMO

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has become a commonly applied procedure for high-risk aortic valve stenosis patients. However, for some patients, this procedure does not result in the expected benefits. Previous studies indicated that it is difficult to predict the beneficial effects for specific patients. We aim to study the accuracy of various traditional machine learning (ML) algorithms in the prediction of TAVI outcomes. METHODS AND RESULTS: Clinical and laboratory data from 1,478 TAVI patients from a single centre were collected. The outcome measures were improvement of dyspnoea and mortality. Three experiments were performed using (1) screening data, (2) laboratory data, and (3) the combination of both. Five well-established ML techniques were implemented, and the models were evaluated based on the area under the curve (AUC). Random forest classifier achieved the highest AUC (0.70) for predicting mortality. Logistic regression had the highest AUC (0.56) in predicting improvement of dyspnoea. CONCLUSIONS: In our single-centre TAVI population, the tree-based models were slightly more accurate than others in predicting mortality. However, ML models performed poorly in predicting improvement of dyspnoea.

6.
Haemophilia ; 24 Suppl 4: 5-19, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29687935

RESUMO

The fifth Åland Island meeting on von Willebrand disease (VWD) was held on the Åland Islands, Finland, from 22 to 24 September 2016-90 years after the first case of VWD was diagnosed in a patient from the Åland Islands in 1926. This meeting brought together experts in the field of VWD to share knowledge and expertise on current trends and challenges in VWD. Topics included the storage and release of von Willebrand factor (VWF), epidemiology and diagnostics in VWD, treatment of VWD, angiogenesis and VWF inhibitors.


Assuntos
Doenças de von Willebrand/diagnóstico , Doenças de von Willebrand/terapia , Humanos , Doenças de von Willebrand/epidemiologia , Doenças de von Willebrand/etiologia
7.
Neth Heart J ; 26(9): 425-432, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30039383

RESUMO

BACKGROUND: Computed tomography angiography (CTA) is required in the work-up for transcatheter aortic valve implantation (TAVI). However, CTA may cause contrast-induced acute kidney injury (CI-AKI). We hypothesised that a short (1 h, 3 ml/kg/h sodium bicarbonate) hydration protocol is not inferior to conventional (24 h, 1 ml/kg/h saline) hydration in avoiding a decline in renal function in patients with impaired renal function. METHODS AND RESULTS: Single-centre randomised non-inferiority trial in patients with impaired renal function who underwent pre-TAVI CTA. Patients were randomised on a 1:1 ratio to short hydration (SHORT; 1 h sodium bicarbonate, 3 ml/kg/h) or conventional hydration (CONV; 24 h saline, 1 ml/kg/h). Outcomes included percentage change in serum creatinine until 2-6 days after CTA with a non-inferiority margin of 10% and an increase on the Borg dyspnoea scale ≥1 point. Seventy-four patients were included. Increase in creatinine was 6 µmol/l (95% CI 2.5-9.3) in the SHORT versus 2 µmol/l (95% CI-1.4 to 6.3) in the CONV arm (p = 0.167). The percentage change was 4.6% (95% CI 2.0-7.3%) in the SHORT arm versus 2.5% (95% CI: 0.8 to 5.8%) in the CONV arm. The difference in percentage increase in creatinine between the two arms was 2.1% (95% CI: 2.0-6.2%; p-value non-inferiority: <0.001). CI-AKI and a need for dialysis were not observed. An increase of ≥1 point on the Borg scale (dyspnoea scale ranging from 1 (lowest) to 10 (highest)) was seen in 1 patient in the SHORT arm versus 5 patients in the CONV arm (2.9% vs 16.1%, p = 0.091). CONCLUSION: For patients with impaired renal function undergoing pre-TAVI CTA, a short 1­h, low-volume hydration protocol with sodium bicarbonate is not inferior to conventional 24-h, high-volume saline hydration.

8.
Neth Heart J ; 26(9): 445-453, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29943117

RESUMO

AIM: In the evolving field of transcatheter aortic valve implantations (TAVI) we aimed to gain insight into trends in patient and procedural characteristics as well as clinical outcome over an 8­year period in a real-world TAVI population. METHODS: We performed a single-centre retrospective analysis of 1,011 consecutive patients in a prospectively acquired database. We divided the cohort into tertiles of 337 patients; first interval: January 2009-March 2013, second interval: March 2013-March 2015, third interval: March 2015-October 2016. RESULTS: Over time, a clear shift in patient selection was noticeable towards lower surgical risks including Society of Thoracic Surgeons predicted risk of mortality score and comorbidity. The frequency of transfemoral TAVI increased (from 66.5 to 77.4%, p = 0.0015). Device success improved (from 62.0 to 91.5%, p < 0.0001) as did the frequency of symptomatic relief (≥1 New York Heart Association class difference) (from 73.8 to 87.1%, p = 0.00025). Complication rates decreased, including in-hospital stroke (from 5.0 to 2.1%, p = 0.033) and pacemaker implantations (from 10.1 to 5.9%, p = 0.033). Thirty-day mortality decreased (from 11.0 to 2.4%, p < 0.0001); after adjustment for patient characteristics, a mortality-risk reduction of 72% was observed (adjusted hazard ratio [HR]: 0.28, 95% confidence interval [CI]: 0.13-0.62). One-year mortality rates decreased (from 23.4 to 11.4%), but this was no longer significant after a landmark point was set at 30 days (mortality from 31 days until 1 year) (adjusted HR: 0.69, 95% CI: 0.41-1.16, p = 0.16). CONCLUSION: A clear shift towards a lower-risk TAVI population and improved clinical outcome was observed over an 8­year period. Survival after TAVI improved impressively, mainly as a consequence of decreased 30-day mortality.

9.
J Microsc ; 259(2): 97-104, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25644989

RESUMO

Electron microscopy is used in biological research to study the ultrastructure at high resolution to obtain information on specific cellular processes. Serial block face-scanning electron microscopy is a relatively novel electron microscopy imaging technique that allows three-dimensional characterization of the ultrastructure in both tissues and cells by measuring volumes of thousands of cubic micrometres yet at nanometre-scale resolution. In the scanning electron microscope, repeatedly an image is acquired followed by the removal of a thin layer resin embedded biological material by either a microtome or a focused ion beam. In this way, each recorded image contains novel structural information which can be used for three-dimensional analysis. Here, we explore focused ion beam facilitated serial block face-scanning electron microscopy to study the endothelial cell-specific storage organelles, the Weibel-Palade bodies, during their biogenesis at the Golgi apparatus. Weibel-Palade bodies predominantly contain the coagulation protein Von Willebrand factor which is secreted by the cell upon vascular damage. Using focused ion beam facilitated serial block face-scanning electron microscopy we show that the technique has the sensitivity to clearly reveal subcellular details like mitochondrial cristae and small vesicles with a diameter of about 50 nm. Also, we reveal numerous associations between Weibel-Palade bodies and Golgi stacks which became conceivable in large-scale three-dimensional data. We demonstrate that serial block face-scanning electron microscopy is a promising tool that offers an alternative for electron tomography to study subcellular organelle interactions in the context of a complete cell.


Assuntos
Técnicas de Preparação Histocitológica/métodos , Imageamento Tridimensional/métodos , Microscopia Eletrônica de Varredura/métodos , Corpos de Weibel-Palade/ultraestrutura , Células Cultivadas , Tomografia com Microscopia Eletrônica/métodos , Células Endoteliais/citologia , Complexo de Golgi/ultraestrutura , Humanos , Microtomia/métodos , Biogênese de Organelas , Inclusão do Tecido , Corpos de Weibel-Palade/fisiologia
11.
J Hosp Infect ; 122: 35-43, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35031393

RESUMO

BACKGROUND: As most automated surveillance (AS) methods to detect healthcare-associated infections (HAIs) have been developed and implemented in research settings, information about the feasibility of large-scale implementation is scarce. AIM: To describe key aspects of the design of AS systems and implementation in European institutions and hospitals. METHODS: An online survey was distributed via e-mail in February/March 2019 among (i) PRAISE (Providing a Roadmap for Automated Infection Surveillance in Europe) network members; (ii) corresponding authors of peer-reviewed European publications on existing AS systems; and (iii) the mailing list of national infection prevention and control focal points of the European Centre for Disease Prevention and Control. Three AS systems from the survey were selected, based on quintessential features, for in-depth review focusing on implementation in practice. FINDINGS: Through the survey and the review of three selected AS systems, notable differences regarding the methods, algorithms, data sources, and targeted HAIs were identified. The majority of AS systems used a classification algorithm for semi-automated surveillance and targeted HAIs were mostly surgical site infections, urinary tract infections, sepsis, or other bloodstream infections. AS systems yielded a reduction of workload for hospital staff. Principal barriers of implementation were strict data security regulations as well as creating and maintaining an information technology infrastructure. CONCLUSION: AS in Europe is characterized by heterogeneity in methods and surveillance targets. To allow for comparisons and encourage homogenization, future publications on AS systems should provide detailed information on source data, methods, and the state of implementation.


Assuntos
Infecção Hospitalar , Infecções Urinárias , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Atenção à Saúde , Hospitais , Humanos , Controle de Infecções/métodos , Infecções Urinárias/epidemiologia , Infecções Urinárias/prevenção & controle
12.
Antimicrob Resist Infect Control ; 9(1): 74, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460887

RESUMO

INTRODUCTION: Current guidelines advocate empirical antibiotic treatment (EAT) in haematological patients with febrile neutropenia. However, the optimal duration of EAT is unknown. In 2011, we have introduced a protocol, promoting discontinuation of carbapenems as EAT after 3 days in most patients and discouraging the standard use of vancomycin. This study assesses the effect of introducing this protocol on carbapenem and vancomycin use in high-risk haematological patients and its safety. METHODS: A retrospective before-after study was performed comparing a cohort from 2007 to 2011 (period I, before restrictive EAT use) with a cohort from 2011 to 2014 (period II, restrictive EAT use). Neutropenic episodes related to chemotherapy or stem cell transplantation (SCT) in patients with acute myeloid leukaemia (AML) or high-risk myelodysplastic syndrome (MDS) were analysed. The primary outcome was the use of carbapenems and vancomycin as EAT during neutropenia, expressed as days of therapy (DOT)/100 neutropenic days and analysed with interrupted time series (ITS). Also the use of other antibiotics was analysed. Safety measurements included 30-day mortality, ICU admittance within 30 days after start of EAT and positive blood cultures with carbapenem-susceptible microorganisms. RESULTS: Three hundred sixty-two neutropenic episodes with a median duration of 18 days were analysed, involving 201 patients. ITS analysis showed decreased carbapenem use with a step change of - 16.1 DOT/100 neutropenic days (95% CI - 26.77 to - 1.39) and an overall reduction of 21.6% (8.7 DOT/100 neutropenic days). Vancomycin use decreased with a step change of - 13.7 DOT/100 neutropenic days (95% CI - 23.75 to - 3.0) and an overall reduction of 54.7% (14.6 DOT/100 neutropenic days). The use of all antibiotics combined decreased from 155.6 to 138 DOT/100 neutropenic days, a reduction of 11.3%. No deaths directly related to early discontinuation of EAT were identified, also no notable difference in ICU-admission (9/116 in period I, 9/152 in period II) and positive blood cultures (4/116 in period I, 2/152 in period II) was detected. CONCLUSION: The introduction of a protocol promoting restrictive use of EAT resulted in reduction of carbapenem and vancomycin use and appears to be safe in AML or high-risk MDS patients with febrile neutropenia during chemotherapy or SCT.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Carbapenêmicos/uso terapêutico , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicas/terapia , Neutropenia/induzido quimicamente , Vancomicina/uso terapêutico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Estudos Controlados Antes e Depois , Feminino , Humanos , Análise de Séries Temporais Interrompida , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Transplante de Células-Tronco/efeitos adversos
13.
Int J Cardiovasc Imaging ; 35(4): 645-651, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30499057

RESUMO

The aim of the current study was to investigate whether stress echocardiography improves selection of patients who might have clinical benefit from percutaneous mitral valve repair with the MitraClip. In total, 39 patients selected for MitraClip implantation underwent preprocedural low-dose stress (dobutamine or handgrip) echocardiography from which stroke volume, ejection fraction and MR grade were measured. Outcome after MitraClip implantation was determined by New York Heart Association classification and Quality of Life questionnaires. Clinical benefit from MitraClip treatment was defined as survival and NYHA class I-II at 6 months follow-up. In total, 36 patients with a technically successful procedure were included in the analysis (mean age 79 ± 8 years, 47% male, 50% functional MR). Clinical benefit was achieved in 18 patients. All seven patients with MR decreasing during stress remained in NYHA III-IV or died within 6 months, while 62% (18 out of 29) of the patients with stable or increased MR during stress had clinical benefit (p = 0.008). Significant increase in Quality of Life on 4/8 subscales of the RAND Short Form-36 questionnaire was observed: Physical Functioning (p < 0.001), Social Functioning (p < 0.001), Mental Health (p = 0.022) and Vitality (p = 0.026) was seen in patients with an increase in stroke volume during stress echocardiography. Patients with a decreased MR during preprocedural stress echocardiography remained more symptomatic than patients with a stable or increased MR during stress. Stress echocardiography may support patient selection for percutaneous mitral valve repair.


Assuntos
Cateterismo Cardíaco , Ecocardiografia sob Estresse , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Agonistas de Receptores Adrenérgicos beta 1/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/mortalidade , Tomada de Decisão Clínica , Dobutamina/administração & dosagem , Exercício Físico , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/mortalidade , Hemodinâmica , Humanos , Masculino , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/mortalidade , Insuficiência da Valva Mitral/fisiopatologia , Seleção de Pacientes , Valor Preditivo dos Testes , Estudos Prospectivos , Qualidade de Vida , Recuperação de Função Fisiológica , Fatores de Risco , Resultado do Tratamento
14.
Int J Tuberc Lung Dis ; 20(10): 1342-1347, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27725045

RESUMO

BACKGROUND: Although isoniazid preventive therapy (IPT) is effective in the prevention of tuberculosis (TB) in people living with the human immunodeficiency virus (PLHIV), patient adherence to this strategy is suboptimal. METHODS: This prospective cohort study was conducted in the HIV/AIDS (acquired immune-deficiency syndrome) out-patient chronic care unit of Dilla University Hospital, Dilla, Ethiopia, from May 2014 to February 2015. Adherence was defined as completion of the 6-month course of treatment with 90% of pills taken, as measured by diary and pill count. Data were collected on potential predictors, including patients' demographic and clinical characteristics. Univariable and multivariable logistic regression models were fitted to identify independent predictors of adherence to IPT. RESULTS: Of 162 PLHIV included, 104 (64.2%) were adherent to IPT. In the final multivariable model, concomitant use of antiretroviral therapy (ART) and/or cotrimoxazole preventive therapy (CPT) was associated with adherence to IPT (OR 2.66, 95%CI 1.15-6.17). Experiencing a high level of HIV stigma and episodes of opportunistic infections tended to be associated with non-adherence to IPT (OR 0.51, 95%CI 0.25-1.04 and OR 0.14, 95%CI 0.02-1.15) in comparison to low stigma and no opportunistic infections, respectively. CONCLUSION: PLHIV receiving ART or CPT were more likely to adhere to IPT.


Assuntos
Antituberculosos/uso terapêutico , Infecções por HIV/epidemiologia , Isoniazida/uso terapêutico , Adesão à Medicação , Profilaxia Pré-Exposição/estatística & dados numéricos , Tuberculose/prevenção & controle , Adulto , Antirretrovirais/uso terapêutico , Etiópia/epidemiologia , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Prospectivos , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
15.
J Hosp Infect ; 92(4): 401-4, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26895616

RESUMO

This observational cohort study assessed the effect of the introduction of antibiotic-impregnated external ventricular drains (AI-EVDs), as opposed to plain silicone EVDs, on the occurrence of ventriculostomy-related infections (VRIs) in two Dutch hospitals, with no other changes to their clinical practice. VRI was defined using the criteria of the Centers for Disease Control and Prevention, and with a culture-based definition. A propensity-score-adjusted competing risks survival analysis showed that introduction of AI-EVDs did not significantly decrease the risk of VRIs in routine care, nor affect the bacterial aetiology, even after adjustment for confounding and competing events.


Assuntos
Antibacterianos/uso terapêutico , Drenagem/métodos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Ventriculostomia/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Resultado do Tratamento , Adulto Jovem
16.
Rev Sci Instrum ; 87(11): 113103, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910317

RESUMO

We report on the design of a cryogenic setup for trapped ion quantum computing containing a segmented surface electrode trap. The heat shield of our cryostat is designed to attenuate alternating magnetic field noise, resulting in 120 dB reduction of 50 Hz noise along the magnetic field axis. We combine this efficient magnetic shielding with high optical access required for single ion addressing as well as for efficient state detection by placing two lenses each with numerical aperture 0.23 inside the inner heat shield. The cryostat design incorporates vibration isolation to avoid decoherence of optical qubits due to the motion of the cryostat. We measure vibrations of the cryostat of less than ±20 nm over 2 s. In addition to the cryogenic apparatus, we describe the setup required for an operation with 40Ca+ and 88Sr+ ions. The instability of the laser manipulating the optical qubits in 40Ca+ is characterized by yielding a minimum of its Allan deviation of 2.4 ⋅ 10-15 at 0.33 s. To evaluate the performance of the apparatus, we trapped 40Ca+ ions, obtaining a heating rate of 2.14(16) phonons/s and a Gaussian decay of the Ramsey contrast with a 1/e-time of 18.2(8) ms.

17.
Neurology ; 44(11): 2040-6, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7969956

RESUMO

"Cerebellar" mutism refers to a specific childhood disorder in which a complete but transient loss of speech, followed by dysarthria, occurs after removal of a cerebellar tumor. We present a consecutive series of 15 children with this disorder, which we prefer to designate "mutism and subsequent dysarthria." The conditions in which it develops suggest also an extracerebellar component of cerebellar mutism. Hydrocephalus at presentation, localization of tumor adjacent to the fourth ventricle, and postsurgical edema of the pontine tegmentum are involved in its development.


Assuntos
Doenças Cerebelares/etiologia , Disartria/etiologia , Mutismo/etiologia , Distúrbios da Fala/etiologia , Astrocitoma/cirurgia , Neoplasias Cerebelares/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Meduloblastoma/cirurgia , Complicações Pós-Operatórias , Síndrome
18.
J Child Neurol ; 14(4): 243-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10334399

RESUMO

In unselected adult patients with brain damage, the Judgment of Line Orientation Test and the Facial Recognition Test are considered valid instruments for detecting right cerebral hemisphere lesions. It is unknown, however, whether this applies to children as well. Performance levels on the Judgment of Line Orientation Test and the Facial Recognition Test of 18 children with acquired left cerebral lesions and 14 children with acquired right cerebral lesions were reviewed. Subjects were unselected for age, sex, or etiology. Age-related norms were obtained in 81 normal controls, aged 7 to 14 years. Judgment of Line Orientation Test and Facial Recognition Test performance levels did not predict the presence of cerebral pathology per se in our unselected groups with demonstrated unilateral cerebral lesions, nor did they contribute to the prediction of the side of the lesion within the two groups with cerebral lesions. These results cast serious doubt on an important aspect of the clinical utility of both tests in children, namely their discriminative validity in the assessment of etiologically unselected populations with brain damage.


Assuntos
Encefalopatias/diagnóstico , Lesões Encefálicas/diagnóstico , Lateralidade Funcional , Testes Neuropsicológicos/normas , Adolescente , Adulto , Criança , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos
19.
Pediatr Neurol ; 15(4): 352-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8972539

RESUMO

Acquired neurologic mutism in childhood is a complex phenomenon occurring in various neurologic conditions with different etiologies. We illustrate its clinical heterogeneity as reflected in a wide range of concomitant behavioral features by presenting 4 children with acquired neurologic mutism. Neuropsychologic examinations revealed differential patterns of defective or preserved phonation, orofacial movements, communicative behavior, and linguistic functions. We propose that detailed neuropsychologic analysis contributes to descriptions of the evolution of the speech impairment beyond the mute phase and the long-term disability. A framework for the clinical evaluation of children is therefore presented.


Assuntos
Afasia Acinética/diagnóstico , Dano Encefálico Crônico/diagnóstico , Afasia Acinética/etiologia , Transtornos da Articulação/diagnóstico , Transtornos da Articulação/etiologia , Dano Encefálico Crônico/complicações , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/etiologia , Masculino , Testes Neuropsicológicos
20.
Pediatr Neurol ; 17(4): 299-307, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9436793

RESUMO

The adult classification of dysarthria correlating with the pathophysiology of the motor systems is usually applied to classify acquired childhood dysarthria. However, the validity of this adult model for children has not been studied systematically. All studies pertaining to analysis of speech features in acquired childhood dysarthria published since 1980 were reviewed. Studies were classified on the basis of neuroradiologic evidence of lesion site and associated motor disorder. This review demonstrates that knowledge of acquired childhood dysarthria is based on a limited number of single case studies, most of which pertain to dysarthria occurring after resection of cerebellar tumor. Definite similarities to adult dysarthria were not evident. Some similarity to acquired childhood dysarthria due to basal ganglia lesions was detected. We conclude that acquired childhood dysarthria requires its own classification.


Assuntos
Disartria/etiologia , Adolescente , Gânglios da Base/patologia , Tronco Encefálico/patologia , Cerebelo/patologia , Criança , Pré-Escolar , Disartria/patologia , Humanos , Desempenho Psicomotor/fisiologia
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