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The response time of a detector stands as a critical parameter in radiation imaging systems. However, the existing parallel plate ionization chamber detector manifests a noteworthy delay in response time, leading to the production of blurred radiation images. To enhance the image quality of radiation imaging systems, it becomes imperative to modify the electrode structure of the detector and consequently reduce the response time. We propose a gas ionization chamber detector incorporating a glass plate, resulting in a notably swift response time. The COMSOL software is employed to calculate the electric and weighting fields within the detector, while Garfield++ software is utilized to derive the output signal, including information on the response time. To validate the simulation data, an experimental ionization chamber underwent testing on a dedicated platform to acquire the output signal. The results revealed that the average electric field intensity in the induced region of the grid detector was increased by at least 10%. The detector response time was reduced to 50%-28% of that of the parallel plate detector. However, this improvement comes at the cost of a decrease in the detector's sensitivity. The incorporation of glass plates in a parallel plate detector offers a substantial improvement in the time response characteristics of a gas ionization chamber detector, thereby suggesting a valuable direction for future advancements in ionization chamber technology.
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The time response characteristic of the detector is crucial in radiation imaging systems. Unfortunately, existing parallel plate ionization chamber detectors have a slow response time, which leads to blurry radiation images. To enhance imaging quality, the electrode structure of the detector must be modified to reduce the response time. This paper proposes a gas detector with a grid structure that has a fast response time. In this study, the detector electrostatic field was calculated using COMSOL, while Garfield++ was utilized to simulate the detector's output signal. To validate the accuracy of simulation results, the experimental ionization chamber was tested on the experimental platform. The results revealed that the average electric field intensity in the induced region of the grid detector was increased by at least 33%. The detector response time was reduced to 27% -38% of that of the parallel plate detector, while the sensitivity of the detector was only reduced by 10%. Therefore, incorporating a grid structure within the parallel plate detector can significantly improve the time response characteristics of the gas detector, providing an insight for future detector enhancements.
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Radiometría , Tiempo de Reacción , Simulación por ComputadorRESUMEN
BACKGROUND: When high thromboembolic and bleeding risks coexist, the former tends to influence physicians' decision making for anti-coagulation therapy. However, the ideal is to weigh the risk of major bleeding and stroke together to ensure effective anti-coagulation treatment, which is a limitation of traditional guideline recommended CHA2DS2-VASc and HAS-BLED. This meta-analysis assesses the performance of the two new scores - ABC and GARFIELD-AF compared to CHA2DS2-VASc and HAS-BLED for major bleeding and stroke outcomes in patients with atrial fibrillation (AF) on anticoagulation therapy. METHODS: MEDLINE and Cochrane central were searched from 2010 to February 2023 that compared GARFIELD-AF and/or ABC with CHA2DS2-VASc and/or HAS-BLED scores using C-statistics to assess their discriminative ability. RESULTS: 12 studies were included in this meta-analysis. When assessing stroke risk prediction, GARFIELD-AF stroke (C-Statistic: 0.71; 95 % CI: 0.70-0.72; I2 = 0 %, p < 0.05) was found to be significantly better than ABC-stroke (C-Statistic: 0.67; 95 % CI: 0.65-0.68; I2 = 0 %, p < 0.05), and CHA2DS2-VASc (C-Statistic: 0.64; 95 % CI: 0.60-0.67; I2 = 92 %, p < 0.05). Additionally, when assessing bleeding risk prediction, ABC-bleeding (C-Statistic: 0.66; 95 % CI: 0.61-0.70; I2 = 84 %, p < 0.05), GARFIELD-AF (C-Statistic: 0.64; 95 % CI: 0.60-0.68; I2 = 95 %, p < 0.05), and HAS-BLED (C-Statistic: 0.64; 95 % CI: 0.62-0.66; I2 = 85 %, p < 0.05) all showed equivalent performances. CONCLUSION: The GARFIELD-AF stroke score showed superior performance to the well-established CHA2DS2-VASc score as well as the ABC-stroke score. Therefore, new guidelines should favor GARFIELD-AF use in clinical practice.
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Fibrilación Atrial , Accidente Cerebrovascular , Humanos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/tratamiento farmacológico , Anticoagulantes , Factores de Riesgo , Medición de Riesgo , Hemorragia/inducido químicamente , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & controlRESUMEN
Although substantial progress has been made in the pathophysiology and management of the post-thrombotic syndrome (PTS), several aspects still need clarification. Among them, the incidence and severity of PTS in the real world, the risk factors for its development, the value of patient's self-evaluation, and the ability to identify patients at risk for severe PTS. Eligible participants (n = 1107) with proximal deep-vein thrombosis (DVT) from the global GARFIELD-VTE registry underwent conventional physician's evaluation for PTS 36 months after diagnosis of their DVT using the Villalta score. In addition, 856 patients completed a Villalta questionnaire at 24 months. Variable selection was performed using stepwise algorithm, and predictors of severe PTS were incorporated into a multivariable risk model. The optimistic adjusted c-index was calculated using bootstrapping techniques. Over 36-months, 27.8% of patients developed incident PTS (mild in 18.7%, moderate in 5.7%, severe in 3.4%). Patients with incident PTS were older, had a lower prevalence of transient risk factors of DVT and a higher prevalence of persistent risk factors of DVT. Self-assessment of overall PTS at 24 months showed an agreement of 63.4% with respect to physician's evaluations at 36 months. The severe PTS multivariable model provided an optimistic adjusted c-index of 0.68 (95% CI 0.59-0.77). Approximately a quarter of DVT patients experienced PTS over 36 months after VTE diagnosis. Patient's self-assessment after 24 months provided added value for estimating incident PTS over 36 months. Multivariable risk analysis allowed good discrimination for severe PTS.
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Síndrome Postrombótico , Tromboembolia Venosa , Trombosis de la Vena , Humanos , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/epidemiología , Trombosis de la Vena/complicaciones , Tromboembolia Venosa/complicaciones , Incidencia , Síndrome Postrombótico/diagnóstico , Síndrome Postrombótico/epidemiología , Síndrome Postrombótico/etiología , Factores de Riesgo , Sistema de RegistrosRESUMEN
Background: Major bleeding in the treatment of atrial fibrillation is closely associated with an increased risk of death and major adverse outcomes in both the short and long term, but all bleeding events are associated with a reduced quality of life. Bleeding events are also known to reduce medication adherence. In this sense, bleeding risk scores are important tools to help predict major bleeding. However, it is not clear which scoring system is superior. Aim: In this study, our aim was to compare bleeding risk scores and to examine the factors associated with bleeding in patients with major bleeding while using vitamin K antagonists. Methods: In this retrospective and single-center study, scoring, laboratory and demographic data were analyzed with SPSS 20.0 statistical program. Results: The mean age of a total of 1434 patients included in our study was 68.2 ± 11.3 years, range was 39-93 years and 769 (53.6%) of these patients were male. Of 588 patients with major bleeding, 93 (15.8%) had intracranial hemorrhage. Logistic regression analysis comparing the scoring systems among themselves revealed that the GARFIELD-AF scoring system had a predictive effect on major bleeding independent of the effect of other scoring systems (OR: 1.532, 95% CI 1.348-1.741, p < 0.001). The area under the curve (AUC) for GARFIELD-AF was 0.690 (0.662-0.718) as a result of the ROC analysis considering the best cut-off point of 3.2% calculated for 2 years. AUC 0.659 (0.630-0.687) for HAS-BLED, AUC 0.636 (0.606-0.665) for ORBIT and AUC 0.611 (0.5810.642) for ATRIA. When we compare the patient group with the control group, it can be said that intracranial hemorrhage occurred independently of INR and TTR values, unlike in the major bleeding group (p:0.129, p:0.545). Conclusion: In patients using vitamin K antagonists for atrial fibrillation, the GARFIELD-AF risk score was found to be superior to important bleeding risk scores such as HAS-BLED, ORBIT and ATRIA in terms of predicting major bleeding. It is an important result that intracranial hemorrhages, which have a special place among major hemorrhages, were independent of INR and TTR levels. It is noteworthy that 8.2% of patients with major bleeding had a history of minor bleeding in the last year.
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Measuring moisture distributions during fast transport processes in thin porous media is a challenging task. In this paper, Ultra Fast Imaging (UFI) NMR is proposed as a valuable measurement technique for investigating moisture uptake in porous media by achieving a temporal resolution of 10â¯ms and spatial resolution between 14.5 and 18⯵m. This paper gives a detailed explanation about the methodology and the interpretation of the signal intensity. It is shown that there exist specific T1- and T2- relaxation time conditions for performing UFI experiments with signal-to-noise ratios that are sufficiently high. In most cases, a contrast agent is required to optimize these relaxation times and achieve the optimal measurement conditions. In the first part of this paper, both CuSO4 and Clariscan are discussed as possible contrast agents. Furthermore, it is shown that the signal intensity can be linked to the moisture content for water based liquids. The second part of this paper covers penetration experiments on porous PVDF membranes. These measurements show that the technique is able to measure moisture profiles during fast capillary penetration and allows to extract moisture front positions. Those front positions follow a linear time behavior in PVDF membranes. Lastly the NMR-measurements showed similar results when compared to scanning absorptometry (ASA).
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Medios de Contraste , Imagen por Resonancia Magnética , Porosidad , Espectroscopía de Resonancia Magnética/métodos , Imagen por Resonancia Magnética/métodosRESUMEN
Air-filled ionization chambers in pulse ion mode can provide precise low-level detection of indoor/outdoor radon. However, it suffers from relatively high collection duration of positive and negative charges as well as environmental changes. In order to overcome these shortcomings, the Garfield++ software which is a powerful toolkit to develop a realistic simulation framework for radiation detectors was applied. Also, Garfield++ interface to Magboltz was used to calculate the gas parameters for air at various humidity conditions for a wide range of electric field strengths in order to compare the results with other available data in the literature. The Garfield++ software was also used to calculate maximum charge collection duration for a wide range of tube radii, wire radii, and electric potentials which are the main parameters affecting the charge collection duration. Furthermore, the influence of environmental conditions including air pressure, temperature, and humidity on the charge collection duration was investigated. The results show that for an air-filled radon ionization chamber with a moderate size (e.g. 1 L) with a bias voltage of hundreds of volts, the time constant of the external circuit can be chosen to be less than 100 ms, which is much lower than the values used in other studies. Therefore, with a proper design of an ionization chamber and its electronic system, it is possible to determine radon activity concentrations of up to a few tens of kBq.m-3 in pulse mode. In conclusion, the data obtained in this study assists in developing radon air-filled ionization chambers in order to determine chamber dimensions and bias voltage as well as designing the readout electronics according to the characteristics required in an intended application.
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Aims: This study aimed to identify relationships in recently diagnosed atrial fibrillation (AF) patients with respect to anticoagulation status, use of guideline-directed medical therapy (GDMT) for comorbid cardiovascular conditions (co-GDMT), and clinical outcomes. The Global Anticoagulant Registry in the FIELD (GARFIELD)-AF is a prospective, international registry of patients with recently diagnosed non-valvular AF at risk of stroke (NCT01090362). Methods and results: Guideline-directed medical therapy was defined according to the European Society of Cardiology guidelines. This study explored co-GDMT use in patients enrolled in GARFIELD-AF (March 2013-August 2016) with CHA2DS2-VASc ≥ 2 (excluding sex) and ≥1 of five comorbidities-coronary artery disease, diabetes mellitus, heart failure, hypertension, and peripheral vascular disease (n = 23 165). Association between co-GDMT and outcome events was evaluated with Cox proportional hazards models, with stratification by all possible combinations of the five comorbidities. Most patients (73.8%) received oral anticoagulants (OACs) as recommended; 15.0% received no recommended co-GDMT, 40.4% received some, and 44.5% received all co-GDMT. At 2 years, comprehensive co-GDMT was associated with a lower risk of all-cause mortality [hazard ratio (HR) 0.89 (0.81-0.99)] and non-cardiovascular mortality [HR 0.85 (0.73-0.99)] compared with inadequate/no GDMT, but cardiovascular mortality was not significantly reduced. Treatment with OACs was beneficial for all-cause mortality and non-cardiovascular mortality, irrespective of co-GDMT use; only in patients receiving all co-GDMT was OAC associated with a lower risk of non-haemorrhagic stroke/systemic embolism. Conclusion: In this large prospective, international registry on AF, comprehensive co-GDMT was associated with a lower risk of mortality in patients with AF and CHA2DS2-VASc ≥ 2 (excluding sex); OAC therapy was associated with reduced all-cause mortality and non-cardiovascular mortality, irrespective of co-GDMT use. Clinical Trial Registration: Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362.
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BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is a worldwide non-interventional study of stroke prevention in patients with non-valvular AF. METHODS AND RESULTS: 52,080 patients with newly diagnosed AF were prospectively enrolled from 2010 to 2016. 4121 (7.9%) of these patients were recruited in DACH [Germany (n = 3567), Austria (n = 465) and Switzerland (n = 89) combined], and 47,959 patients were from 32 countries in other regions worldwide (ORW). Hypertension was most prevalent in DACH and ORW (85.3% and 75.6%, respectively). Diabetes, hypercholesterolaemia, carotid occlusive disease and vascular disease were more prevalent in DACH patients vs ORW (27.6%, 49.4%, 5.8% and 29.0% vs 21.7%, 40.9%, 2.8% and 24.5%). The use of non-vitamin K antagonist oral anticoagulants (NOACs) increased more in DACH over time. Management of vitamin K antagonists was suboptimal in DACH and ORW (time in therapeutic range of INR ≥ 65% in 44.6% and 44.4% of patients or ≥ 70% in 36.9% and 36.0% of patients, respectively). Adjusted rates of cardiovascular mortality and MI/ACS were higher in DACH while non-haemorrhagic stroke/systemic embolism was lower after 2-year follow-up. CONCLUSIONS: Similarities and dissimilarities in AF management and clinical outcomes are seen in DACH and ORW. The increased use of NOAC was associated with a mismatch of risk-adapted anticoagulation (over-and-undertreatment) in DACH. Suboptimal control of INR requires educational activities in both regional groups. Higher rates of cardiovascular death in DACH may reflect the higher risk profile of these patients and lower rates of non-haemorrhagic stroke could be associated with increased NOAC use.
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Fibrilación Atrial , Accidente Cerebrovascular , Humanos , Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/complicaciones , Austria/epidemiología , Suiza/epidemiología , Administración Oral , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Sistema de Registros , Factores de RiesgoRESUMEN
The grid inefficiency (GI) of Frisch grid ionization chambers (FGICs) must be considered in the case of accurate energy measurements. A Monte-Carlo model has been developed based on the Garfield and SRIM toolkits to investigate the GI of FGIC. It could simulate the charge signals from different electrodes without considering the electrical noises and random effects in the experiments. Computations made with the weighting potential and charge signals of FGIC exemplify the possibilities of this model. The GI values obtained with different methods showed the difference among the existing approaches in the literature. In addition, the results of homogeneous deformations of one wire over one grid period showed that deformation in the grid plane caused more distortion on GI than that perpendicular to the grid plane. An individual experiment was also carried out with a compound alpha source (241Am and 243Am) to validate the feasibility of this model. The results showed that the raw pulses and GI values obtained from the simulation agreed well with those measured from the experiment. The present work showed that this Monte-Carlo model could be well applied to investigate such type of detector, which could provide great conveniences for future work to measure the total kinetic energy of the fission fragments.
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Sistemas de Computación , Radiometría , Simulación por Computador , Electrodos , Método de Montecarlo , Radiometría/métodosRESUMEN
Reaction and transport processes in thin layers of between 10 and 1000 µm are important factors in determining their performance, stability and degradation. In this review, we discuss the potential of high-gradient Nuclear Magnetic Resonance (NMR) as a tool to study both reactions and transport in these layers spatially and temporally resolved. As the NMR resolution depends on gradient strength, the high spatial resolution required in submillimeter layers can only be achieved with specially designed high-gradient setups. Three different high-gradient setups exist: STRAFI (STRay FIeld), GARField (Gradient-At-Right-angles-to-Field) and MOUSE (MObile Universal Surface Explorer). The aim of this review is to provide a detailed overview of the three techniques and their ability to visualize reactions and transport processes using physical observable properties such as hydrogen density, diffusion, T1- and T2-relaxation. Finally, different examples from literature will be presented to illustrate the wide variety of applications that can be studied and the corresponding value of the techniques.
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AIMS: To determine whether the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) integrated risk tool predicts mortality, non-haemorrhagic stroke/systemic embolism, and major bleeding for up to 2 years after new-onset AF and to assess how this risk tool performs compared with CHA2DS2-VASc and HAS-BLED. METHODS AND RESULTS: Potential predictors of events included demographic and clinical characteristics, choice of treatment, and lifestyle factors. A Cox proportional hazards model was identified for each outcome by least absolute shrinkage and selection operator methods. Indices were evaluated in comparison with CHA2DS2-VASc and HAS-BLED risk predictors. Models were validated internally and externally in ORBIT-AF and Danish nationwide registries. Among the 52 080 patients enrolled in GARFIELD-AF, 52 032 had follow-up data. The GARFIELD-AF risk tool outperformed CHA2DS2-VASc for all-cause mortality in all cohorts. The GARFIELD-AF risk score was superior to CHA2DS2-VASc for non-haemorrhagic stroke, and it outperformed HAS-BLED for major bleeding in internal validation and in the Danish AF cohort. In very low- to low-risk patients [CHA2DS2-VASc 0 or 1 (men) and 1 or 2 (women)], the GARFIELD-AF risk score offered strong discriminatory value for all the endpoints when compared to CHA2DS2-VASc and HAS-BLED. The GARFIELD-AF tool also included the effect of oral anticoagulation (OAC) therapy, thus allowing clinicians to compare the expected outcome of different anticoagulant treatment decisions [i.e. no OAC, non-vitamin K antagonist (VKA) oral anticoagulants, or VKAs]. CONCLUSIONS: The GARFIELD-AF risk tool outperformed CHA2DS2-VASc at predicting death and non-haemorrhagic stroke, and it outperformed HAS-BLED for major bleeding in overall as well as in very low- to low-risk group patients with AF. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier for GARFIELD-AF: NCT01090362, ORBIT-AF I: NCT01165710; ORBIT-AF II: NCT01701817.
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Fibrilación Atrial , Accidente Cerebrovascular , Anticoagulantes/uso terapéutico , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Femenino , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Humanos , Masculino , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiologíaRESUMEN
Randomized controlled trials (RCTs) are considered the gold standard for estimating the effectiveness of a treatment. However, in many instances they are impractical to conduct because of time limitations, cost restrictions, or ethical reasons. As a consequence, non-randomized observational studies have an important role in comparative effectiveness and safety research since they can address issues that would not be possible using conventional RCT methodology. Observational studies can be strategically designed to reduce the risk of potential sources of bias by emulating the design principles of an equivalent but ideal randomized trial - the target trial - that would answer the research question of interest. In this article, we review some of the necessary components of observational studies required for valid causal inference within the framework of target trial emulation, so as to avoid common methodological pitfalls of study design. We discuss the assumptions of consistency, time-zero specification, exchangeability and positivity. To illustrate these concepts in a context where existing knowledge is well-established through clinical trials, we evaluate and compare the treatment effects of vitamin K antagonists (VKA) against no VKA (No VKA) on the treatment of atrial fibrillation from two real-world observational studies, namely the GARFIELD-AF and ORBIT-AF registries. Results are compared with those of published RCTs.
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Fibrilación Atrial , Accidente Cerebrovascular , Anticoagulantes/uso terapéutico , Fibrilación Atrial/complicaciones , Investigación sobre la Eficacia Comparativa , Humanos , Estudios Observacionales como Asunto , Sistema de Registros , Accidente Cerebrovascular/etiología , Factores de TiempoRESUMEN
The paper presents the development of the IMUMETER sensor, designed to study the dynamics of aircraft movement, in particular, to measure the ground performance of the aircraft. A motivation of this study was to develop a sensor capable of airplane motion measurement, especially for airfield performance, takeoff and landing. The IMUMETER sensor was designed on the basis of the method of artificial neural networks. The use of a neural network is justified by the fact that the automation of the measurement of the airplane's ground distance during landing based on acceleration data is possible thanks to the recognition of the touchdown and stopping points, using artificial intelligence. The hardware is based on a single-board computer that works with the inertial navigation platform and a satellite navigation sensor. In the development of the IMUMETER device, original software solutions were developed and tested. The paper describes the development of the Convolution Neural Network, including the learning process based on the measurement results during flight tests of the PZL 104 Wilga 35A aircraft. The ground distance of the test airplane during landing on a grass runway was calculated using the developed neural network model. Additionally included are exemplary measurements of the landing distance of the test airplane during landing on a grass runway. The results obtained in this study can be useful in the development of artificial intelligence-based sensors, especially those for the measurement and analysis of aircraft flight dynamics.
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Inteligencia Artificial , Redes Neurales de la Computación , Aceleración , AeronavesRESUMEN
AIMS: Heart failure (HF) and atrial fibrillation (AF) may coexist and influence each other. However, characteristics, anticoagulant treatment, and outcomes of contemporary AF patients with concurrent HF are ill-defined. This study analyses characteristics, treatment, and 2 year outcomes in newly diagnosed Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) patients with vs. without HF. METHODS AND RESULTS: GARFIELD-AF is the world's largest observational AF patient study. At enrolment, 11 758 of 52 072 patients (22.6%) had HF; 76.3% were New York Heart Association class II-III. Patients with HF had comparable demographics, blood pressure, and heart rate but more likely had permanent (15.6% vs. 11.9%) or persistent AF (18.9% vs. 13.8%), acute coronary syndromes (16.7% vs. 8.9%), vascular disease (40.8% vs. 20.2%), and moderate-to-severe chronic kidney disease (14.6% vs. 9.0%) than those without. Anticoagulant prescription was similar between the two groups. At 2 year follow-up, patients with HF showed a greater risk of all-cause mortality [hazard ratio (HR), 2.06; 95% confidence interval (CI), 1.91-2.21; P < 0.0001], cardiovascular mortality (HR, 2.91; 95% CI, 2.58-3.29; P < 0.0001), acute coronary syndromes (HR, 1.25; 95% CI, 1.02-1.52; P = 0.03), and stroke/systemic embolism (HR, 1.24; 95% CI, 1.07-1.43; P = 0.0044). Major bleeding rate was comparable (adjusted HR, 1.00; 95% CI, 0.84-1.18; P = 0.968). Among patients without HF at baseline, incidence of new HF was low [0.69 (95% CI, 0.63-0.75) per 100 person-years], whereas propensity to develop worsening HF was higher in those with HF [1.62 (95% CI, 1.45-1.80) per 100 person-years]. CONCLUSIONS: Patients with AF and HF have a high risk of all-cause and cardiovascular mortality and stroke/systemic embolism and may develop worsening HF.
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Fibrilación Atrial , Insuficiencia Cardíaca , Accidente Cerebrovascular , Anticoagulantes , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Humanos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiologíaRESUMEN
The Global Anticoagulant Registry in the Field-Atrial Fibrillation (GARFIELD-AF) examined real-world practice in a total of 57,149 (5069 retrospective, 52,080 prospective) patients with newly diagnosed AF at risk of stroke/systemic embolism, enrolled at over 1000 centers in 35 countries. It aimed to capture data on AF burden, patients' clinical profile, patterns of clinical practice and antithrombotic management, focusing on stroke/systemic embolism prevention, uptake of new oral anticoagulants, impact on death and bleeding. GARFIELD-AF set new standards for quality of data collection and analysis. A total of 36 peer-reviewed articles were already published and 73 abstracts presented at international congresses, covering treatment strategies, geographical variations in baseline risk and therapies, adverse outcomes and common comorbidities such as heart failure. A risk prediction tool as well as innovative observational studies and artificial intelligence methodologies are currently being developed by GARFIELD-AF researchers. Clinical Trial Registration: NCT01090362 (ClinicalTrials.gov).
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Fibrilación Atrial , Accidente Cerebrovascular , Anticoagulantes/uso terapéutico , Inteligencia Artificial , Fibrilación Atrial/complicaciones , Fibrilación Atrial/epidemiología , Humanos , Estudios Prospectivos , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & controlRESUMEN
U.S. Army doctor Daniel Smith Lamb was a significant figure in the history of American pathology during its formative years. For 55 years (1865-1920), Lamb performed hundreds of autopsies in and around Washington, D.C. and personally collected over 1,500 gross pathology specimens for the Army Medical Museum. His work began at the close of the Civil War and continued on through World War I, contributing substantially to gross pathological and histological studies that documented wartime pathology, thus further contributing to the training of Army doctors. Specimens he collected also include material from autopsies he conducted on President James Garfield, his assassin Charles Guiteau, and other historical figures. Under the auspices of the Army Medical Museum, he conducted autopsies across the city of Washington for the museum's collection, many of which survive to this day at the National Museum of Health and Medicine. He served under 12 U.S. Army Surgeons General and 11 Museum Curators and was noted to be a steadying influence during a time of constant leadership changes at that institution. Lamb was known throughout Washington, D.C. as an advocate of medical education for African-Americans and women. While working at the Museum, he simultaneously served for 46 years as professor of anatomy at Howard University (1877-1923). He wrote seminal histories of the institutions with which he was associated and in so doing also contributed significantly to the study of the history of medicine.
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Anatomía/historia , Historia de la Medicina , Medicina Militar/historia , Médicos/historia , Autopsia/historia , District of Columbia , Docentes/historia , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Museos/historia , Facultades de Medicina/historia , Estados UnidosRESUMEN
Background Using data from the GARFIELD - AF (Global Anticoagulant Registry in the FIELD -Atrial Fibrillation), we evaluated the impact of chronic kidney disease ( CKD ) stage on clinical outcomes in patients with newly diagnosed atrial fibrillation ( AF ). Methods and Results GARFIELD - AF is a prospective registry of patients from 35 countries, including patients from Asia (China, India, Japan, Singapore, South Korea, and Thailand). Consecutive patients enrolled (2013-2016) were classified with no, mild, or moderate-to-severe CKD , based on the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative guidelines. Data on CKD status and outcomes were available for 33 024 of 34 854 patients (including 9491 patients from Asia); 10.9% (n=3613) had moderate-to-severe CKD , 16.9% (n=5595) mild CKD , and 72.1% (n=23 816) no CKD . The use of oral anticoagulants was influenced by stroke risk (ie, post hoc assessment of CHA 2 DS 2- VAS c score), but not by CKD stage. The quality of anticoagulant control with vitamin K antagonists did not differ with CKD stage. After adjusting for baseline characteristics and antithrombotic use, both mild and moderate-to-severe CKD were independent risk factors for all-cause mortality. Moderate-to-severe CKD was independently associated with a higher risk of stroke/systemic embolism, major bleeding, new-onset acute coronary syndrome, and new or worsening heart failure. The impact of moderate-to-severe CKD on mortality was significantly greater in patients from Asia than the rest of the world ( P=0.001). Conclusions In GARFIELD - AF , moderate-to-severe CKD was independently associated with stroke/systemic embolism, major bleeding, and mortality. The effect of moderate-to-severe CKD on mortality was even greater in patients from Asia than the rest of the world. Clinical Trial Registration URL : http://www.clinicaltrials.gov . Unique identifier: NCT 01090362.
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Anticoagulantes/administración & dosificación , Fibrilación Atrial/tratamiento farmacológico , Sistema de Registros , Insuficiencia Renal Crónica/terapia , Medición de Riesgo/métodos , Administración Oral , Anciano , Anciano de 80 o más Años , Asia/epidemiología , Fibrilación Atrial/complicaciones , Fibrilación Atrial/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/mortalidad , Factores de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Tasa de Supervivencia/tendencias , Factores de TiempoRESUMEN
This paper describes airfield measurement of forces and moments that act on a landing gear wheel. For the measurement, a wheel force sensor was used. The sensor was designed and built based on strain gage technology and was embedded in the left landing gear wheel of a test aircraft. The sensor is capable of measuring simultaneously three perpendicular forces and three moments and sends data to a handheld device wirelessly. For the airfield tests, the sensor was installed on a PZL 104 Wilga 35A multipurpose aircraft. The aircraft was towed at a "marching man" speed and the measurements were performed at three driving modes: Free rolling, braking, and turning. The paper contains results obtained in the field measurements performed on a grassy runway of the Rzeszów Jasionka Aerodrome, Poland. Rolling resistance of aircraft tire, braking friction, as well as aligning moment were analyzed and discussed with respect to surface conditions.