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1.
J Comput Chem ; 45(7): 392-404, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38014502

RESUMO

Molecular quantum-dot cellular automata (QCA) is a low-power computing paradigm that may offer ultra-high device densities and THz-speed switching at room temperature. A single mixed-valence (MV) molecule acts as an elementary QCA device known as a cell. Cells coupled locally via the electrostatic field form logic circuits. However, previously-synthesized ionic MV molecular cells are affected by randomly-located, nearby neutralizing counterions that can bias device states or change device characteristics, causing incorrect computational results. This ab initio study explores how non-biasing counterions affect individual molecular cells. Additionally, we model two novel neutral, zwitterionic MV QCA molecules designed to avoid biasing and other undesirable counterionic effects. The location of the neutralizing counterion is controlled by integrating one counterion into each cell at a well-defined, non-biasing location. Each zwitterionic QCA candidate molecule presented here has a fixed, integrated counterion, which neutralizes the mobile charges used to encode the device state.

2.
BMC Public Health ; 24(1): 2400, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232770

RESUMO

BACKGROUND: The effectiveness of crisis response can be influenced by various structural, cultural, and functional aspects within a social system. This study uses a configurational approach to identify combinations of sociopolitical conditions that lead to a high case fatality rate (CFR) of COVID-19 in OECD countries. METHODS: A Fuzzy set qualitative comparative analysis (QCA) is conducted on a sample of 38 OECD countries. The outcome to be explained is high COVID-19 CFR. The five potentially causal conditions are level of democracy, state capacity, trust in government, health expenditure per capita, and the median age of population. A comprehensive QCA robustness test protocol is applied, which includes sensitivity ranges, fit-oriented robustness, and case-oriented robustness tests. RESULTS: None of the causal conditions in both the presence and negation form were found to be necessary for high or low levels of COVID-19 CFR. Two different combinations of sociopolitical conditions were usually sufficient for the occurrence of a high CFR of COVID-19 in OECD countries. Low state capacity and low trust in government are part of both recipes. The entire solution formula covers 84 percent of the outcome.  Some countries have been identified as contradictory cases. The explanations for their COVID-19 CFR require more in-depth case studies. CONCLUSIONS: From a governance perspective, the weakness of government in effectively implementing policies, and the citizens' lack of confidence in their government, combined with other structural conditions, serve as barriers to mounting an effective response to COVID-19. These findings can support the idea that the effects of social determinants of COVID-19 outcomes are interconnected and reinforcing.


Assuntos
COVID-19 , Organização para a Cooperação e Desenvolvimento Econômico , Política , COVID-19/mortalidade , COVID-19/epidemiologia , Humanos , SARS-CoV-2 , Governo
3.
Risk Anal ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38922992

RESUMO

Due to the pervasive uncertainty in human society, super large and megacities are increasingly prone to becoming high-risk areas. However, the construction of urban resilience in this new era lacks sufficient research on the core conditions and complex interactive mechanisms governing it. Hence, this study proposes a specialized event-oriented framework for governing urban resilience in China based on the pressure-state-response (PSR) theory. We examined COVID-19 cases in 30 cities across China and analyzed the distribution of prevention and control achievements between high-level and non-high-level conditions. Our findings reveal the following key points: (1) High-level achievements in COVID-19 prevention and control rely on three condition configurations: non-pressure-responsive type, pressure-state type, and pressure-responsive type. (2) High economic resilience may indicate a robust state of urban systems amid demographic pressures. In cities experiencing fewer event pressure factors, the application of digital technology plays a crucial role in daily urban management. (3) The implementation of flexible policies proves beneficial in mitigating the impact of objective pressure conditions, such as environmental factors, on urban resilience.

4.
J Environ Manage ; 360: 121217, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788411

RESUMO

With rapid economic growth, the issue of water pollution has become increasingly prominent, and there is a consensus that river basin management systems and cross-regional management coordination mechanisms need improving. In this study, 171 transboundary sections of the Yangtze River Basin were matched with the data of 57 cities to construct panel data from 2015 to 2021. Based on the four-dimensional framework of environment-determination-process-resources, the dynamic qualitative comparative analysis (QCA) method is used to identify the key influencing factors and action paths of water pollution collaborative governance effects. The results show that a single antecedent condition is not necessary to achieve efficient collaborative governance effects, and only the "number of collaborative governance" and "scale of collaboration" conditions played important roles. There are five paths that can achieve efficient collaborative governance effects: economy-oriented, ecology-oriented, technology-oriented, government-oriented, and all-oriented. Additionally, heterogeneous results show that the impact of the regional governance intention on efficient collaborative governance effect is limited in the middle and upstream sections of the Yangtze River Basin, while the downstream sections are more dependent on the basic condition of the basin. The results can help promote effective cross-regional collaboration in the Yangtze River Basin, provide scientific basis for regions to formulate targeted governance measures, and provide models for governance in other regions.


Assuntos
Rios , Poluição da Água , China , Poluição da Água/prevenção & controle , Conservação dos Recursos Naturais
5.
BMC Nurs ; 23(1): 282, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671443

RESUMO

BACKGROUND: Errors of omissions affect the quality of nursing care in hospitals. The Missed Nursing Care Model explains that the reasons for missed care are linked with 1) demand for patient care, 2) labor resource allocation, 3) material resource allocation, and 4) relationship and communication factors. Scientific evidence points to a lack of adequate nursing staffing as the most important factor triggering missed care. However, it remains unclear how the different theoretical reasons for missed care are interlinked with reports on missed care from the perspective of nurses in acute care settings. The aim of this study was to explore non-trivial configurations of reasons for missed care that are associated with missed care interventions from the perspective of nurses working in general units in Austrian hospitals. METHODS: A cross-sectional study was conducted. Data collection was performed using the revised MISSCARE-Austria questionnaire. Our sample consisted of 401 nurses who provided complete data. Data were analyzed using qualitative comparative analysis. Configurational models of contextual factors, reasons for missed care, and missed nursing interventions were analyzed. RESULTS: In our study contextual factors were not consistent precursors of the reasons for missed care. Missed care was consistently present when the demand for patient care was high. A lack of labor resources, in combination with the other known reasons for missed care, was consistently observed when missed care occurred. Different configurations of reasons were found to be non-trivially associated with different types and frequencies of missed care. CONCLUSIONS: To understand the complexity of the causal mechanisms of missed care, complexity theory may be necessary. Accordingly, a theoretical framework that acknowledges that complex systems, such as missed care, are composed of multiple interacting causal components must be further developed to guide new methodical approaches to enlighten its causal mechanisms.

6.
Int J Mol Sci ; 24(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37239920

RESUMO

Millions of SARS-CoV-2 whole genome sequences have been generated to date. However, good quality data and adequate surveillance systems are required to contribute to meaningful surveillance in public health. In this context, the network of Spanish laboratories for coronavirus (RELECOV) was created with the main goal of promoting actions to speed up the detection, analyses, and evaluation of SARS-CoV-2 at a national level, partially structured and financed by an ECDC-HERA-Incubator action (ECDC/GRANT/2021/024). A SARS-CoV-2 sequencing quality control assessment (QCA) was developed to evaluate the network's technical capacity. QCA full panel results showed a lower hit rate for lineage assignment compared to that obtained for variants. Genomic data comprising 48,578 viral genomes were studied and evaluated to monitor SARS-CoV-2. The developed network actions showed a 36% increase in sharing viral sequences. In addition, analysis of lineage/sublineage-defining mutations to track the virus showed characteristic mutation profiles for the Delta and Omicron variants. Further, phylogenetic analyses strongly correlated with different variant clusters, obtaining a robust reference tree. The RELECOV network has made it possible to improve and enhance the genomic surveillance of SARS-CoV-2 in Spain. It has provided and evaluated genomic tools for viral genome monitoring and characterization that make it possible to increase knowledge efficiently and quickly, promoting the genomic surveillance of SARS-CoV-2 in Spain.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Espanha/epidemiologia , Filogenia , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/genética , Genômica , Mutação
7.
Environ Manage ; 71(3): 670-684, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35604427

RESUMO

It is common understanding that to address pressing environmental issues and ensure sustainable environmental management innovative solutions are required. Many studies have striven to understand which governance conditions enable generation of innovative solutions. However, there are very few studies in the field of management and public administration studies that investigate the combined, interactive effects of a suit of conditions on the likelihood of innovative solutions. This article uses the method of qualitative comparative analysis (QCA) to investigate the complex causality of collaborative governance and innovative solutions. More specifically, it examines the combination of conditions of collaborative process, leadership, institutional design and knowledge sharing, and their joint effects on the presence or absence of innovative solutions. An analysis of 16 cases of environmental endeavors with a goal of generating innovative solutions and extracted from Collaborative Governance Case Database shows that there are 3 possible configurations or paths leading to innovative solutions. Various combinations of the above-mentioned conditions can in fact be sufficient for generating innovative solutions. The configurations provide insight into which collaborative conditions deserve attention when aiming for innovation in the field of sustainable environmental management.

8.
Kolner Z Soz Sozpsychol ; : 1-28, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37360992

RESUMO

In Europe, individualist societies, in which people more highly value independence, have fewer people who are lonely. Yet these societies also have more people who live alone, a strong determinant of loneliness. Evidence suggests that some unrecognized societal-level resources or characteristics can explain this. We uncover multiple pathways toward a lower degree of loneliness among European societies using an ideal method for this purpose, fuzzy-set qualitative comparative analysis. Using data from the 2014 wave of the European Social Survey and other sources, we analyzed loneliness outcomes among 26 European societies. Our findings suggest two necessary conditions for a low degree of loneliness: high internet access and high association participation. Further, three pathways are sufficient for achieving less loneliness at the societal level. Most societies that have less loneliness follow both the welfare support and cultural support pathways. The third path, commercial provision, is mutually exclusive with welfare support because the former requires a weak welfare state. The surest policy for building societies that have lower rates of loneliness includes the expansion of internet accessibility, the fostering of civil society through association participation and volunteering, and a welfare state that protects potentially vulnerable populations while funding opportunities for social interaction. This article further contributes methodologically by demonstrating "configurational robustness testing," a more comprehensive means to implement current best practices for fuzzy-set qualitative comparative analysis robustness testing.

9.
Catheter Cardiovasc Interv ; 100(6): 964-970, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36321612

RESUMO

BACKGROUND: Angiography-based vessel fractional flow reserve (vFFR) demonstrated a strong correlation with invasive fractional flow reserve (FFR) in both a pre- and post-percutaneous coronary intervention (PCI) setting. However, the role of vFFR and its correlation with post-PCI FFR in chronic coronary occlusions (CTO) has not been evaluated yet. We sought to investigate the diagnostic performance of post-PCI vFFR with post-PCI FFR as a reference in patients undergoing successful CTO PCI. METHODS: Between March 2016 and April 2020, a total of 80 patients from the FFR-SEARCH (prospective registry) and FFR REACT (randomized controlled trial) studies underwent successful CTO recanalization with post-PCI FFR measurements. RESULTS: A total of 50 patients (median age 66 (interquartile range [IQR]: 56-74) years, 76% were male) were eligible for the analysis. Median post-PCI FFR was 0.89 (IQR: 0.84-0.94), while median post-PCI vFFR was 0.91 (IQR: 0.85-0.94) (p 0.10). Suboptimal physiological results, defined as FFR and vFFR <0.90, were identified in 26 (52%) and in 21 (42%) patients, respectively. A strong correlation (r = 0.82) was found between vFFR and FFR with a mean bias of 0.013 ± 0.051. Receiver-operating characteristics curve analysis revealed an excellent accuracy of vFFR in predicting FFR <0.90 (area under the curve: 0.97; 95% confidence interval: 0.93-1.00). CONCLUSION: Post-PCI vFFR shows a good correlation with post-PCI FFR and a high diagnostic accuracy for post-PCI FFR ≤0.90 in patients undergoing successful PCI of a CTO lesion.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Angiografia Coronária/métodos , Valor Preditivo dos Testes , Resultado do Tratamento , Doença da Artéria Coronariana/diagnóstico
10.
BMC Med Res Methodol ; 22(1): 333, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36564706

RESUMO

BACKGROUND: Modern configurational comparative methods (CCMs) of causal inference, such as Qualitative Comparative Analysis (QCA) and Coincidence Analysis (CNA), have started to make inroads into medical and health research over the last decade. At the same time, these methods remain unable to process data on multi-morbidity, a situation in which at least two chronic conditions are simultaneously present. Such data require the capability to analyze complex effects. Against a background of fast-growing numbers of patients with multi-morbid diagnoses, we present a new member of the family of CCMs with which multiple conditions and their complex conjunctions can be analyzed: Combinational Regularity Analysis (CORA). METHODS: The technical heart of CORA consists of algorithms that have originally been developed in electrical engineering for the analysis of multi-output switching circuits. We have adapted these algorithms for purposes of configurational data analysis. To demonstrate CORA, we provide several example applications, both with simulated and empirical data, by means of the eponymous software package CORA. Also included in CORA is the possibility to mine configurational data and to visualize results via logic diagrams. RESULTS: For simple single-condition analyses, CORA's solution is identical with that of QCA or CNA. However, analyses of multiple conditions with CORA differ in important respects from analyses with QCA or CNA. Most importantly, CORA is presently the only configurational method able to simultaneously explain individual conditions as well as complex conjunctions of conditions. CONCLUSIONS: Through CORA, problems of multi-morbidity in particular, and configurational analyses of complex effects in general, come into the analytical reach of CCMs. Future research aims to further broaden and enhance CORA's capabilities for refining such analyses.


Assuntos
Algoritmos , Humanos
11.
Nanotechnology ; 33(46)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35944440

RESUMO

Quantum-dot cellular automata (QCA) is a nanoscale, transistor-less device technology. A single molecule may provide an elementary QCA device known as a cell. Molecular redox centers function as quantum dots, and the configuration of mobile charge on the dots encodes device states useful for classical computing. Molecular QCA may support ultra-high device densities and THz-scale switching speeds at room temperature. An applied electric field may be used to clock molecular QCA, providing power gain to boost weakened signals, as well as quasi-adiabatic device operation for minimal power dissipation in QCA devices and circuits. A zwitterionic, Y-shaped, three-dot molecule may function as a field-clocked QCA cell. We focus on the design of a counterion built into the center of the cell.Ab initiocomputations demonstrate that choice of counterion determines the number of mobile charges for encoding the device state on the three quantum dots. We useB5H52-orB4CH5-as the central counterionic linker for two different Y-shaped, three-dot QCA molecules. While both molecules support the desired device states, the number of trapped charges in the counterion determines the number of mobile holes on the molecular quantum dots. This, in turn, determines whether the device state is encoded by a hole or an electron. This choice of encoding determines how the molecular QCA cell responds to a clocking field. The two counterions studied here lead to two QCA molecules with opposite responses to the clock, similar to the complementary responses of PMOS and NMOS transistors to gated voltage control.

12.
BMC Cardiovasc Disord ; 22(1): 178, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35436856

RESUMO

BACKGROUND: Computed tomography angiography (CTA) is a cornerstone in the pre- transcatheter aortic valve replacement (TAVI) assessment. We evaluated the diagnostic performance of CTA and coronary artery calcium score (CACS) for CAD evaluation compared to invasive coronary angiography in a cohort of TAVI patients. METHODS: In consecutive TAVI patients without prior coronary revascularization and device implants, CAD was assessment by quantitative analysis in CTA. (a) Patients with non-evaluable segments were classified as obstructive CAD. (b) In patients with non-evaluable segments a CACS cut-off of 100 was applied for obstructive CAD. The reference standard was quantitative invasive coronary angiography (QCA, i.e. ≥ 50% stenosis). RESULTS: 100 consecutive patients were retrospectively included, age was 82.3 ± 6.5 years and 30% of patients had CAD. In 16% of the patients, adequate visualization of the entire coronary tree (all 16 segments) was possible with CTA, while 84% had at least one segment which was not evaluable for CAD analysis due to impaired image quality. On a per-patient analysis, where patients with low image quality were classified as CAD, CTA showed a sensitivity of 100% (95% CI 88.4-100.0), specificity of 11.4% (95% CI 5.1-21.3), PPV of 32.6% (95% CI 30.8-34.5), NPV of 100% and diagnostic accuracy of 38% (95% CI 28.5-48.3) for obstructive CAD. When applying a combined approach of CTA (in patients with good image quality) and CACS (in patients with low image quality), the sensitivity and NPV remained at 100% and obstructive CAD could be ruled out in 20% of the TAVI patients, versus 8% using CTA alone. CONCLUSION: In routinely acquired pre-TAVI CTA, the image quality was insufficient in a high proportion of patients for the assessment of the entire coronary artery tree. However, when adding CACS in patients with low image quality to quantitative CTA assessment in patients with good image quality, obstructive CAD could be ruled-out in 1/5 of the patients and may therefore constitute a strategy to streamline pre-procedural workup, and reduce risk, radiation and costs in selected TAVI patients without prior coronary revascularization or device implants.


Assuntos
Estenose da Valva Aórtica , Doença da Artéria Coronariana , Estenose Coronária , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/etiologia , Estenose da Valva Aórtica/cirurgia , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Humanos , Estudos Retrospectivos , Substituição da Valva Aórtica Transcateter/efeitos adversos
13.
Sensors (Basel) ; 23(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36616616

RESUMO

In this study, we propose a quantum structure of an associative memory cell for effective data learning based on artificial intelligence. For effective learning of related data, content-based retrieval and storage rather than memory address is essential. A content-addressable memory (CAM), which is an efficient memory cell structure for this purpose, in a quantum computing environment, is designed based on quantum-dot cellular automata (QCA). A CAM cell is composed of a memory unit that stores information, a match unit that performs a search, and a structure, using an XOR gate or an XNOR gate in the match unit, that shows good performance. In this study, we designed an XNOR gate with a multilayer structure based on electron interactions and proposed a QCA-based CAM cell using it. The area and time efficiency are verified through a simulation using QCADesigner, and the quantum cost of the proposed XOR gate and CAM cell were reduced by at least 70% and 15%, respectively, when compared to the latest research. In addition, we physically proved the potential energy owing to the interaction between the electrons inside the QCA cell. We also proposed an additional CAM circuit targeting the reduction in energy dissipation that overcomes the best available designs. The simulation and calculation of power dissipation are performed by QCADesigner-E and it is confirmed that more than 27% is reduced.


Assuntos
Autômato Celular , Metodologias Computacionais , Inteligência Artificial , Teoria Quântica , Eletrônica
14.
J Environ Manage ; 315: 115189, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35523071

RESUMO

The role of cultural ecosystem services (CES) is vital to consider when developing ecological sustainable development policies that can improve the well-being of humans. Research on CES has increased in recent years; however, few studies have explored the complex mechanisms driving perceptions of CES and the factors influencing those perceptions. In areas with unique landforms and fragile ecological environments, this type of research is difficult and rare. To address this research gap, this focuses on a typical karst area Guilin Xingping in China, evaluating residents' perceptions of local CES, and applying qualitative comparative analysis (QCA) to explore the driving mechanism behind those perceptions. We found that the satisfaction of material needs is a prerequisite and basis for further improving residents' spiritual perceptions and pursuits. Residents' socio-economic level, understanding of resource importance, and economic value determine whether residents can fully perceive the value of CES. Optimizing the ability of managers, improving relevant systems, and improving the experience with and understanding of ecosystems have a more than 50% probability of improving perceptions related to CES. The research shows that the combination of multiple antecedents can achieve a high level of perceptions related to CES. Managers can refer to the best path for policy regulation based on the actual situation. Finally, this study provides a new policy scheme for promoting ecological sustainable development and improving residents' well-being, and can provide insights to inform the sustainable development of other karst areas.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Humanos , Satisfação Pessoal , Políticas
15.
Catheter Cardiovasc Interv ; 97(5): 825-832, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32478462

RESUMO

OBJECTIVE: To evaluate the diagnostic performance of quantitative flow ratio (QFR) related to fractional flow reserve (FFR) and resting distal-to-aortic pressure ratio (resting Pd/Pa) concordance. BACKGROUND: QFR is a method for computation of FFR based on standard coronary angiography. It is unclear how QFR is performed in patients with discordance between FFR and resting pressure ratios (distal-to-aortic pressure ratio [Pd/Pa]). MATERIALS AND METHODS: The main comparison was the diagnostic performance of QFR with FFR as reference stratified by correspondence between FFR and resting Pd/Pa. Secondary outcome measures included distribution of clinical or procedural characteristics stratified by FFR and resting Pd/Pa correspondence. RESULTS: Four prospective studies matched the inclusion criteria. Analysis was performed on patient level data reaching a total of 759 patients and 887 vessels with paired FFR, QFR, and resting Pd/Pa. Median FFR was 0.85 (IQR: 0.77-0.90). Diagnostic accuracy of QFR with FFR as reference was higher if FFR corresponded to resting Pd/Pa: accuracy 90% (95% CI: 88-92) versus 72% (95% CI: 64-80), p < .001, and sAUC 0.95 (95% CI: 0.92-0.96) versus 0.73 (95% CI: 0.69-0.77), p < .001. Resting Pd/Pa and FFR discordance were related to age, sex, hypertension, and lesion severity. CONCLUSION: Diagnostic performance of QFR with FFR as reference is reduced for lesions with discordant FFR (≤0.80) and resting Pd/Pa (≤0.92) measurements.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Pressão Arterial , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Resultado do Tratamento
16.
Catheter Cardiovasc Interv ; 98(1): E69-E77, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33600069

RESUMO

BACKGROUND: This study sought to evaluate the clinical outcomes of patients treated with magnesium-based bioresorbable scaffolds (MgBRS) in the context of acute coronary syndromes (ACS) at long-term follow-up (24 months). The study also aims to investigate the MgBRS performance by angiography and the healing and bioresorption pattern by optical coherence tomography (OCT) at 18 months. METHODS: Between December 2016 and December 2018, a total of 90 patients admitted for ACS and treated with MgBRS (Magmaris, Biotronik AG, Bülach, Switzerland) were enrolled in a multicenter prospective study. Clinical follow-up was performed in all patients at 24 months and angiographic and OCT follow-up in 51.5% of patients at 18 months. Serial OCT was available in 33 patients (36.7%). RESULTS: At a 2-year follow-up, 88.8% were free of symptoms, no cardiac death was reported, and the device-oriented composite event (DOCE): consisting of cardiac death, target vessel myocardial infarction, and target lesion revascularization (TLR) was 13.3%. Stent thrombosis and TLR were observed in 2.2 and 11.1%, respectively. Binary restenosis was observed in 21.7% of cases and in-stent late lumen loss was 0.61 ± 0.75 mm. By serial OCT imaging, the minimal lumen area was significantly reduced greater than 40% (from 6.12 ± 1.59 to 3.5 ± 1.55 mm2, p < .001). At follow-up, area stenosis was 44.33 ± 23.07% and half of the patients presented indiscernible struts. The principal observed mechanism of restenosis was scaffold collapse. CONCLUSIONS: At long-term follow-up, MgBRS implantation in ACS patients showed a high rate of DOCE, mainly caused by clinically driven TLR. MgBRS restenosis was caused by scaffold collapse in most of the cases.


Assuntos
Síndrome Coronariana Aguda , Stents Farmacológicos , Intervenção Coronária Percutânea , Implantes Absorvíveis , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/terapia , Angiografia Coronária , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Desenho de Prótese , Sirolimo , Tomografia de Coerência Óptica , Resultado do Tratamento
17.
Catheter Cardiovasc Interv ; 97(4): E495-E501, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32725862

RESUMO

OBJECTIVES: We aimed to evaluate the feasibility of using three dimensional-quantitative coronary angiography (3D-QCA) based fractional flow reserve (FFR) (vessel fractional flow reserve [vFFR], CAAS8.1, Pie Medical Imaging) and to correlate vFFR values with intravascular ultrasound (IVUS) for the evaluation of intermediate left main coronary artery (LMCA) stenosis. BACKGROUND: 3D-QCA derived FFR indices have been recently developed for less invasive functional lesion assessment. However, LMCA lesions were vastly under-represented in first validation studies. METHODS: This observational single-center cohort study enrolled consecutive patients with stable angina, unstable angina, or non-ST-segment elevation myocardial infarction and nonostial, intermediate grade LMCA stenoses who underwent IVUS evaluation. vFFR was computed based on two angiograms with optimal LMCA stenosis projection and correlated with IVUS-derived minimal lumen area (MLA). RESULTS: A total of 256 patients with intermediate grade LMCA stenosis evaluated with IVUS were screened for eligibility; 147 patients met the clinical inclusion criteria and had a complete IVUS LMCA footage available, of them, 63 patients (63 lesions) underwent 3D-QCA and vFFR analyses. The main reason for screening failure was insufficient quality of the angiogram (51 patients,60.7%). Mean age was 65 ± 11 years, 75% were male. Overall, mean MLA within LMCA was 8.77 ± 3.17 mm2 , while mean vFFR was 0.87 ± 0.09. A correlation was observed between vFFR and LMCA MLA (r = .792, p = .001). The diagnostic accuracy of vFFR ≤0.8 in identifying lesions with MLA < 6.0 mm2 (sensitivity 98%, specificity 71.4%, area under the curve (AUC) 0.95, 95% confidence interval (CI) 0.89-1.00, p = .001) was good. CONCLUSIONS: In patients with good quality angiographic visualization of LMCA and available complete LMCA IVUS footage, 3D-QCA based vFFR assessment of LMCA disease correlates well to LMCA MLA as assessed by IVUS.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Estudos de Coortes , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Humanos , Masculino , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia de Intervenção
18.
Nanotechnology ; 33(11)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34875643

RESUMO

Mixed-valence compounds may provide molecular devices for an energy-efficient, low-power, general-purpose computing paradigm known as quantum-dot cellular automata (QCA). Multiple redox centers on mixed-valence molecules provide a system of coupled quantum dots. The configuration of mobile charge on a double-quantum-dot (DQD) molecule encodes a bit of classical information robust at room temperature. When arranged in non-homogeneous patterns (circuits) on a substrate, local Coulomb coupling between molecules enables information processing. While single-electron transistors and single-electron boxes could provide low-temperature solutions for reading the state of a ∼1 nm scale molecule, we propose a room-temperature read-out scheme. Here, DQD molecules are designed with slightly dissimilar quantum dots.Ab initiocalculations show that the binary device states of an asymmetric molecule have distinct Raman spectra. Additionally, the dots are similar enough that mobile charge is not trapped on either dot, allowing device switching driven by the charge configuration of a neighbor molecule. A technique such as tip-enhanced Raman spectroscopy could be used to detect the state of a circuit comprised of several QCA molecules.

19.
Voluntas ; 32(4): 731-749, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34092933

RESUMO

Most international development projects that aim to eradicate poverty and improve the quality of life of people in low- and middle-income countries are implemented through a collaborative network of multiple parties, including non-governmental organizations (NGOs). However, how network effectiveness in international development projects can be achieved remains unclear. Using fuzzy-set qualitative comparative analysis, this study explores the causal conditions of network effectiveness of 37 international development projects implemented by South Korean NGOs based on a theoretical lens of collaborative networks. Findings revealed two causal configurations for network effectiveness. Even under a lack of network management capacity and unintegrated networks, or under resource deficiency and lack of network management capacity, high-level local capacity or high-quality collaboration among partners was shown to produce network effectiveness. An in-depth analysis of two cases with successful network effectiveness was also conducted to achieve a more thorough and comprehensive understanding of the causal conditions. The findings suggest practical solutions to manage collaborative networks and compensate for deficiencies of diverse conditions to improve network effectiveness.

20.
Int J Equity Health ; 19(1): 129, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33100213

RESUMO

BACKGROUND: Social and community participation is a fundamental component of the development of renewed primary healthcare (PHC). With the recognition of health as a right, such participation is a significant part of the design of public policies aimed at this sector. These policies contribute not only to overcoming inequity in the provision of this type of services but also to a reduction in social inequalities as a whole. Through a comparative analysis, this study aimed to explain the conditions through which ethnic-rural territories of the Colombian Pacific coast participate in health to contribute to the generation of policies and programs in territories with similar conditions. METHODS: The work was developed through the use of multiple techniques and strategies for information collection and analysis. These include several semi-structured interviews, multiple observation exercises and analysis based on a set theory, i.e., qualitative comparative analysis (QCA). The latter aims to develop a model that provides a count of the main causal combinations that allow high community participation in health. RESULTS: Key findings include how the trajectory of social mobilization and existence of a robust community social fabric became two critical conditions for community participation in the context of social exclusion. The presence of variables such as the implementation of PHC, guarantee of social rights, and trust in institutions, is underestimated as sufficient causal conditions for obtaining this result. Therefore, it is essential to recognize the existence, validity, and importance of processes, experiences, and resourcefulness of political natures, which aim at transforming the daily reality of the inhabitants of these communities. These also set a potential space and scenario for managing the communities' main problems, including health, in the absence of institutionality that guarantees access to their social rights. CONCLUSION: This study points out the importance of understanding community participation as a political activity, expanding exchange dynamics and dialogs between institutions, rulers, and communities to provide social responses in health and well-being to communities and to understand local realities and their own community dynamics.


Assuntos
Participação da Comunidade/estatística & dados numéricos , Atenção Primária à Saúde/organização & administração , População Rural , Colômbia , Humanos , Política , Pesquisa Qualitativa
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