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3.
Rev. esp. cardiol. (Ed. impr.) ; 75(11): 906-913, nov. 2022. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-211712

RESUMO

Introducción y objetivos La disección coronaria espontánea (DCE) es una causa poco común de infarto agudo de miocardio (IAM). En este estudio se comparan la mortalidad y los reingresos hospitalarios de los pacientes con IAM-DCE e IAM de otras etiologías (IAM-NDCE). Métodos Se calcularon las razones de mortalidad hospitalaria y de reingresos a los 30 días estandarizadas por riesgo (RAMER y RARER respectivamente) utilizando el Conjunto Mínimo Básico de Datos del Sistema Nacional de Salud español (2016-2019). Resultados Se hallaron 806 eventos de IAM-DCE y 119.425 de IMA-NDCE. Los IAM-DCE se produjeron en pacientes más jóvenes y más frecuentemente mujeres que los IAM-NDCE. La mortalidad bruta fue menor (el 3 frente al 7,6%; p<0,001) y la RAMER, mayor (el 7,6±1,7 frente al 7,4±1,7%; p=0,019) en los IAM-DCE. Tras emparejamiento por puntuación de propensión (806 parejas), la mortalidad fue similar en ambos grupos (AdjOR=1,15; IC95%, 0,61-2,2; p=0,653). La tasa bruta de reingresos de los pacientes con IAM-DCE a 30 días fue similar (el 4,6 frente al 5%; p=0,67), mientras que la RARER fue menor (el 4,7±1 frente al 4,8±1%; p=0,015). Tras el emparejamiento por puntuación de propensión (715 parejas), la tasa de ingresos fue similar en ambos grupos (AdjOR=1,14; IC95%, 0,67-1,98; p=0,603). Conclusiones La mortalidad hospitalaria y los reingresos a los 30 días de los pacientes con IAM-DCE es similar a la de los IAM-NDCE cuando el riesgo se ajusta a las características basales de la población. Estos datos resaltan la necesidad de optimizar el manejo, tratamiento y seguimiento clínico de los pacientes con DCE (AU)


Introduction and objectives Spontaneous coronary artery dissection (SCAD) is a rare cause of acute myocardial infarction (AMI). We sought to compare the results on in-hospital mortality and 30-day readmission rates among patients with AMI-SCAD vs AMI due to other causes (AMI-non-SCAD). Methods Risk-standardized in-hospital mortality (rIMR) and risk-standardized 30-day readmission ratios (rRAR) were calculated using the minimum dataset of the Spanish National Health System (2016-2019). Results A total of 806 episodes of AMI-SCAD were compared with 119 425 episodes of AMI–non-SCAD. Patients with AMI-SCAD were younger and more frequently female than those with AMI–non-SCAD. Crude in-hospital mortality was lower (3% vs 7.6%; P<.001) and rIMR higher (7.6±1.7% vs 7.4±1.7%; P=.019) in AMI-SCAD. However, after propensity score adjustment (806 pairs), the mortality rate was similar in the 2 groups (AdjOR, 1.15; 95%CI, 0.61-2,2; P=.653). Crude 30-day readmission rates were also similar in the 2 groups (4.6% vs 5%, P=.67) whereas rRAR were lower (4.7±1% vs 4.8%±1%; P=.015) in patients with AMI-SCAD. Again, after propensity score adjustment (715 pairs) readmission rates were similar in the 2 groups (AdjOR, 1.14; 95%CI, 0.67–1.98; P=.603). Conclusions In-hospital mortality and readmission rates are similar in patients with AMI-SCAD and AMI–non-SCAD when adjusted for the differences in baseline characteristics. These findings underscore the need to optimize the management, treatment, and clinical follow-up of patients with SCAD (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Doença das Coronárias/mortalidade , Mortalidade Hospitalar , Estudos Retrospectivos , Registros Médicos , Espanha/epidemiologia
4.
Astrobiology ; 22(9): 1047-1060, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35972349

RESUMO

Landed missions to icy worlds with a subsurface liquid water ocean must meet planetary protection requirements and ensure a sufficiently small likelihood of any microorganism-bearing part of the landed element reaching the ocean. A higher bound on this likelihood is set by the potential for radioisotope thermoelectric generator (RTG) power sources, the hottest possible landed element, to melt through the ice shell and reach the ocean. In this study, we quantify this potential as a function of three key parameters: surface temperature, ice shell thickness (i.e., heat flux through the shell), and thickness of a porous (insulating) snow or regolith cover. Although the model we describe can be applied to any ocean world, we present results in the context of a landed mission concept to the south polar terrain of Saturn's moon Enceladus. In this particular context, we discuss planetary protection considerations for landing site selection. The likelihood of forward microbial contamination of Enceladus' ocean by an RTG-powered landed mission can be made sufficiently low to not undermine compliance with the planetary protection policy.


Assuntos
Meio Ambiente Extraterreno , Gelo , Oceanos e Mares , Planetas , Radioisótopos
5.
Rev. esp. cardiol. (Ed. impr.) ; 75(6): 515-522, Jun. 2022. ilus
Artigo em Espanhol | IBECS | ID: ibc-205109

RESUMO

Introducción y objetivos: La disección coronaria espontánea (DCE) es una causa rara de síndrome coronario agudo. La mayor parte de los pacientes con DCE son tratados empíricamente con bloqueadores beta (BB) y antiagregantes plaquetarios (AP). El estudio BA-SCAD (bloqueadores beta y agentes antiplaquetarios en pacientes con disección coronaria espontánea) es un ensayo clínico académico, pragmático, diseñado con metodología PROBE (prospective randomized open blinded endpoint), con el patrocinio de la Sociedad Española de Cardiología, para conocer la eficacia del tratamiento farmacológico en pacientes con DCE. Métodos: Mediante un diseño factorial 2 × 2, se aleatorizará a 600 pacientes (1:1/1:1) a: a) BB (sí/no) y b) tratamiento con AP «corto» (1 mes) frente a tratamiento antiagregante plaquetario doble y «prolongado» (12 meses). Se aleatorizará a BB (sí/no) solo a los pacientes con fracción de eyección del ventrículo izquierdo conservada, ya que a los pacientes con fracción de eyección reducida se los tratará con BB de acuerdo con las guías actuales. De modo similar, se aleatorizará al estrato de AP solo a los pacientes en tratamiento conservador (sin revascularización), ya que los que requieran intervención coronaria recibirán tratamiento antiagregante plaquetario doble durante 1 año. El objetivo primario de valoración incluye muerte, infarto de miocardio, accidente cerebrovascular, revascularización coronaria, DCE recurrente y hospitalización no planeada por síndrome coronario agudo o insuficiencia cardiaca al año de seguimiento. El objetivo de seguridad es la hemorragia. Todos los pacientes serán seguidos anualmente. Se desarrollará un programa exhaustivo de subestudios adicionales (clínicos, de imagen, de revascularización, de biomarcadores, inflamatorios, inmunológicos, farmacogenéticos y genéticos) para garantizar una visión completa de esta entidad tan especial y compleja (AU)


introduction y objectives: Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome. Most patients are empirically treated with beta-blockers and antiplatelet drugs. The Beta-blockers and Antiplatelet agents in patients with Spontaneous Coronary Artery Dissection (BA-SCAD) is an academic, pragmatic, prospective, randomized, open-label, blinded-endpoint clinical trial, performed under the auspices of the Spanish Society of Cardiology, to assess the efficacy of pharmacological therapy in patients with SCAD. Methods: Using a 2 x 2 factorial design, 600 patients will be randomized (1:1/1:1) to: a) beta-blockers (yes/no) and b) “short” (1 month) vs “prolonged” (12 months) antiplatelet therapy. Only patients with preserved left ventricular ejection fraction will be randomized to beta-blockers (yes/no) because patients with reduced left ventricular ejection fraction will receive beta-blockers according to current guidelines. Similarly, only conservatively managed patients (ie, no coronary intervention) will be randomized to the antiplatelet stratum, as patients requiring coronary interventions will receive 1-year dual antiplatelet therapy. The primary efficacy endpoint includes a composite of death, myocardial infarction, stroke, coronary revascularization, recurrent SCAD, and unplanned hospitalization for acute coronary syndrome or heart failure at 1 year. The primary safety endpoint will be bleeding. All patients will be clinically followed up yearly. A comprehensive set of additional substudies (clinical, imaging, revascularization, biomarkers, inflammatory, immunologic, pharmacogenetics, and genetic) will be conducted to ensure a holistic view of this unique and challenging clinical entity.Conclusions: The results of the BA-SCAD randomized clinical trial will advance our knowledge in the treatment of patients with SCAD (AU)


Assuntos
Humanos , Síndrome Coronariana Aguda/tratamento farmacológico , Antagonistas Adrenérgicos beta/uso terapêutico , Anomalias dos Vasos Coronários/complicações , Anomalias dos Vasos Coronários/diagnóstico por imagem , Inibidores da Agregação Plaquetária/uso terapêutico , Angiografia Coronária
6.
Rev. esp. cardiol. (Ed. impr.) ; 75(5): 412-420, mayo 2022.
Artigo em Espanhol | IBECS | ID: ibc-205089

RESUMO

Introducción y objetivos: Una profundidad más alta del implante percutáneo de una válvula aórtica autoexpandible minimiza el daño en el sistema de conducción y puede reducir las tasas de marcapasos permanente a 30 días. El objetivo es determinar la seguridad y la eficacia de modificar la técnica de implante clásica para el reemplazo percutáneo de la válvula aórtica a una técnica de proyección de superposición de cúspides (PSC) para lograr una profundidad más alta del implante y reducir la necesidad de marcapasos permanente. Métodos: Desde marzo de 2017 se incluyó a 226 pacientes consecutivos: 113 tratados con técnica de implante PSC frente a 113 casos consecutivos previos con implante clásico. La profundidad del implante se evaluó mediante 3 métodos en todos los pacientes (cúspide no coronaria a válvula cardiaca percutánea (VCP); media de cúspide no coronaria y cúspide coronaria izquierda a VCP y el borde más profundo de cúspide coronaria izquierda y cúspide no coronaria a VCP). Resultados: El grupo de PSC presentó una profundidad del implante menor que el del grupo de implante clásico (4,8±2,2 frente a 5,7±3,1 mm; p=0,011; 5,8±3,1 frente a 6,5±2,4 mm; p=0,095; 7,1±2,8 frente a 7,4±3,2 mm; p=0,392). A los 30 días de seguimiento, 40 pacientes (17,7%) requirieron el implante de marcapasos permanente, menos en el grupo de PSC (el 12,4 frente al 23%; p=0,036). La técnica de implante PSC protegió contra el evento principal (OR=0,45; IC95%, 0,21-0,97; p=0,043), con parecidos éxito del procedimiento y complicaciones. Conclusiones: La técnica de implante PSC es una simple modificación en el protocolo que proporciona una profundidad del implante más alta de la prótesis valvular autoexpandible con menores alteraciones de la conducción y tasas de marcapasos permanente (AU)


Introduction and objectives: This study aimed to determine the safety and efficacy of modifying the classic implantation technique for aortic transcatheter heart valve (THV) implantation to a cusp-overlap-projection (COP) technique to achieve a higher implantation depth and to reduce the burden of new permanent pacemaker implantation (PPMI) at 30 days. Aortic self-expanding THV carries an elevated risk for PPMI. A higher implantation depth minimizes the damage in the conduction system and may reduce PPMI rates. Methods: From March 2017, 226 patients were consecutively included: 113 patients were treated using the COP implantation technique compared with the previous 113 consecutive patients treated using the classic technique. In all patients, implantation depth was assessed by 3 methods (noncoronary cusp to the THV, mean of the noncoronary cusp and the left coronary cusp to the THV, and the deepest edge from the left coronary cusp and the noncoronary cusp to the THV). Results: The COP group had a lower implantation depth than the group treated with the classic technique (4.8 mm± 2.2 vs 5.7 mm± 3.1; P=.011; 5.8 mm± 3.1 vs 6.5 mm± 2.4; P=.095; 7.1 mm± 2.8 vs 7.4 mm±3.2; P=.392). Forty patients (17.7%) required a new PPMI after the 30-day follow-up but this requirement was significantly lower in the COP group (12.4% vs 23%, P=.036). The COP implantation technique consistently protected against the main event (OR, 0.45; 95%CI, 0.21-0.97; P=.043), with similar procedural success rates and complications. Conclusions: The COP implantation technique is a simple modification of the implantation protocol and provides a higher implantation depth of self-expanding-THV with lower conduction disturbances and PPMI rates (AU)


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Estudos Prospectivos , Desenho de Prótese , Projetos Piloto , Resultado do Tratamento
7.
Astrobiology ; 22(6): 685-712, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35290745

RESUMO

Cassini revealed that Saturn's Moon Enceladus hosts a subsurface ocean that meets the accepted criteria for habitability with bio-essential elements and compounds, liquid water, and energy sources available in the environment. Whether these conditions are sufficiently abundant and collocated to support life remains unknown and cannot be determined from Cassini data. However, thanks to the plume of oceanic material emanating from Enceladus' south pole, a new mission to Enceladus could search for evidence of life without having to descend through kilometers of ice. In this article, we outline the science motivations for such a successor to Cassini, choosing the primary science goal to be determining whether Enceladus is inhabited and assuming a resource level equivalent to NASA's Flagship-class missions. We selected a set of potential biosignature measurements that are complementary and orthogonal to build a robust case for any life detection result. This result would be further informed by quantifications of the habitability of the environment through geochemical and geophysical investigations into the ocean and ice shell crust. This study demonstrates that Enceladus' plume offers an unparalleled opportunity for in situ exploration of an Ocean World and that the planetary science and astrobiology community is well equipped to take full advantage of it in the coming decades.


Assuntos
Saturno , Exobiologia , Meio Ambiente Extraterreno/química , Gelo , Planetas
8.
Rev Esp Anestesiol Reanim (Engl Ed) ; 69(3): 129-133, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35279416

RESUMO

BACKGROUND AND OBJECTIVE: Cardiogenic shock (CS) mortality remains very high and mechanical circulatory support (MCS) may provide an effective alternative of treatment in selected patients. The aim of this study is to analyse the results of a multidisciplinary team care program (including anaesthesiologists, cardiologists, cardiothoracic surgeons, and intensivists) in CS patients who required MCS, in a tertiary centre without a heart transplant (HT) program. METHODS: Prospective observational study that sought to analyse the characteristics and survival to discharge predictors in a consecutive CS patients cohort treated with MCS. RESULTS: A total of 48 patients were included. Mean age was 61 ± 14 years. Before MCS, 45.8% of the patients presented with cardiac arrest. A 54.2% 30-day survival and 45.8% overall survival to discharge, was found. Age and vasoactive-inotropic score were independent predictors of mortality. CONCLUSIONS: A multidisciplinary team-care based MCS program in CS patients is feasible and may achieve favourable results in a centre without HT program.


Assuntos
Oxigenação por Membrana Extracorpórea , Transplante de Coração , Coração Auxiliar , Idoso , Oxigenação por Membrana Extracorpórea/efeitos adversos , Humanos , Pessoa de Meia-Idade , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Resultado do Tratamento
9.
Rev. esp. anestesiol. reanim ; 69(3): 129-133, Mar 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-205039

RESUMO

Antecedentes y objetivo: El shock cardiogénico (SC) conlleva una elevada mortalidad, y algunos pacientes pueden beneficiarse del uso de soporte circulatorio mecánico (SCM). El objetivo de este estudio es analizar los resultados de un programa multidisciplinar (constituido por anestesiología y reanimación, cardiología, cirugía cardiaca y medicina intensiva) de atención a pacientes en SC que precisaron SCM en un hospital terciario sin programa de trasplante cardiaco. (TC). Materiales y métodosEstudio prospectivo observacional que analiza las características y predictores de supervivencia hospitalaria de los pacientes con SC que precisaron SCM. Resultados: Se incluyeron 48 pacientes. Edad media 61±14años. El 45,8% presentaron parada cardiaca previa al implante. La supervivencia a 30días fue del 54,2% y la supervivencia al alta hospitalaria, del 45,8%. La edad y la escala de vasoactivos inotrópicos fueron predictores independientes de mortalidad. Conclusiones: La instauración de un programa multidisciplinar de SCM en un centro sin programa de TC es factible y aplicable a pacientes con SC, con resultados favorables en cuanto a supervivencia hospitalaria.(AU)


Background and objective: Cardiogenic shock (CS) mortality remains very high and mechanical circulatory support (MCS) may provide an effective alternative of treatment in selected patients. The aim of this study is to analyse the results of a multidisciplinary team care program (including anaesthesiologists, cardiologists, cardiothoracic surgeons, and intensivists) in CS patients who required MCS, in a tertiary centre without a heart transplant (HT) program. Methods: Prospective observational study that sought to analyse the characteristics and survival to discharge predictors in a consecutive CS patients cohort treated with MCS. Results: A total of 48 patients were included. Mean age was 61 ± 14 years. Before MCS, 45.8% of the patients presented with cardiac arrest. A 54.2% 30-day survival and 45.8% overall survival to discharge, was found. Age and vasoactive-inotropic score were independent predictors of mortality. Conclusions: A multidisciplinary team-care based MCS program in CS patients is feasible and may achieve favourable results in a centre without HT program.(AU)


Assuntos
Humanos , Masculino , Choque Cardiogênico , Transplante de Coração , Sobrevivência , Previsões , Cardiologia , Serviço Hospitalar de Cardiologia , Cirurgia Torácica , Anestesiologia , Reanimação Cardiopulmonar , Estudos Prospectivos
13.
Environ Microbiol ; 23(7): 3335-3344, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33817931

RESUMO

Astrobiology is mistakenly regarded by some as a field confined to studies of life beyond Earth. Here, we consider life on Earth through an astrobiological lens. Whereas classical studies of microbiology historically focused on various anthropocentric sub-fields (such as fermented foods or commensals and pathogens of crop plants, livestock and humans), addressing key biological questions via astrobiological approaches can further our understanding of all life on Earth. We highlight potential implications of this approach through the articles in this Environmental Microbiology special issue 'Ecophysiology of Extremophiles'. They report on the microbiology of places/processes including low-temperature environments and chemically diverse saline- and hypersaline habitats; aspects of sulphur metabolism in hypersaline lakes, dysoxic marine waters, and thermal acidic springs; biology of extremophile viruses; the survival of terrestrial extremophiles on the surface of Mars; biological soils crusts and rock-associated microbes of deserts; subsurface and deep biosphere, including a salticle formed within Triassic halite; and interactions of microbes with igneous and sedimentary rocks. These studies, some of which we highlight here, contribute to our understanding of the spatiotemporal reach of Earth'sfunctional biosphere, and the tenacity of terrestrial life. Their findings will help set the stage for future work focused on the constraints for life, and how organisms adapt and evolve to circumvent these constraints.


Assuntos
Exobiologia , Meio Ambiente Extraterreno , Planeta Terra , Ecossistema , Microbiologia Ambiental , Humanos
14.
Astrobiology ; 21(7): 802-812, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33848439

RESUMO

The possibility of biological transfer between planetary bodies is seldom factored into life detection strategies, although the actuality of such an event would have profound implications for how we interpret potential biosignatures found on other worlds. This article addresses the possibility of life on Mars in the context of a biological transfer and an independent genesis of life. The phylogenetic tree of life on Earth is used as a blueprint to interpret evidence of life and as a guideline to determine the likelihood that potential biosignatures could be expressed by martian organisms. Several transfer scenarios are considered, depending on the timing of transfer with respect to the evolution of life on Earth. The implications of each transfer scenario and an independent genesis of life on the biochemical nature of the resulting martian organisms are discussed. The analysis highlights how conceding the possibility of a biological transfer has practical implications for how we search for evidence of life, both in terms of the quality of potential biosignatures and the likelihood that certain biosignatures might be expressed. It is concluded that a degree of uncertainty on the origin of martian organisms might be unavoidable, particularly in the absence of a biochemical context.


Assuntos
Exobiologia , Marte , Meio Ambiente Extraterreno , Filogenia , Planetas
17.
Remote Sens (Basel) ; 12(1): 50, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32355570

RESUMO

In recent years, the deployment of satellites and unmanned aerial vehicles (UAVs) has led to production of enormous amounts of data and to novel data processing and analysis techniques for monitoring crop conditions. One overlooked data source amid these efforts, however, is incorporation of 3D information derived from multi-spectral imagery and photogrammetry algorithms into crop monitoring algorithms. Few studies and algorithms have taken advantage of 3D UAV information in monitoring and assessment of plant conditions. In this study, different aspects of UAV point cloud information for enhancing remote sensing evapotranspiration (ET) models, particularly the Two-Source Energy Balance Model (TSEB), over a commercial vineyard located in California are presented. Toward this end, an innovative algorithm called Vegetation Structural-Spectral Information eXtraction Algorithm (VSSIXA) has been developed. This algorithm is able to accurately estimate height, volume, surface area, and projected surface area of the plant canopy solely based on point cloud information. In addition to biomass information, it can add multi-spectral UAV information to point clouds and provide spectral-structural canopy properties. The biomass information is used to assess its relationship with in situ Leaf Area Index (LAI), which is a crucial input for ET models. In addition, instead of using nominal field values of plant parameters, spatial information of fractional cover, canopy height, and canopy width are input to the TSEB model. Therefore, the two main objectives for incorporating point cloud information into remote sensing ET models for this study are to (1) evaluate the possible improvement in the estimation of LAI and biomass parameters from point cloud information in order to create robust LAI maps at the model resolution and (2) assess the sensitivity of the TSEB model to using average/nominal values versus spatially-distributed canopy fractional cover, height, and width information derived from point cloud data. The proposed algorithm is tested on imagery from the Utah State University AggieAir sUAS Program as part of the ARS-USDA GRAPEX Project (Grape Remote sensing Atmospheric Profile and Evapotranspiration eXperiment) collected since 2014 over multiple vineyards located in California. The results indicate a robust relationship between in situ LAI measurements and estimated biomass parameters from the point cloud data, and improvement in the agreement between TSEB model output of ET with tower measurements when employing LAI and spatially-distributed canopy structure parameters derived from the point cloud data.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31359901

RESUMO

Tests of the most recent version of the two-source energy balance model have demonstrated that canopy and soil temperatures can be retrieved from high-resolution thermal imagery captured by an unmanned aerial vehicle (UAV). This work has assumed a linear relationship between vegetation indices (VIs) and radiometric temperature in a square grid (i.e., 3.6 m × 3.6 m) that is coarser than the resolution of the imagery acquired by the UAV. In this method, with visible, near infrared (VNIR), and thermal bands available at the same high-resolution, a linear fit can be obtained over the pixels located in a grid, where the x-axis is a vegetation index (VI) and the y-axis is radiometric temperature. Next, with an accurate VI threshold that separates soil and vegetation pixels from one another, the corresponding soil and vegetation temperatures can be extracted from the linear equation. Although this method is simpler than other approaches, such as TSEB with Priestly-Taylor (TSEB-PT), it could be sensitive to VIs and the parameters that affect VIs, such as shadows. Recent studies have revealed that, on average, the values of VIs, such as normalized difference vegetation index (NDVI) and leaf area index (LAI), that are located in sunlit areas are greater than those in shaded areas. This means that involving or compensating for shadows will affect the linear relationship parameters (slope and bias) between radiometric temperature and VI, as well as thresholds that separate soil and vegetation pixels. This study evaluates the impact of shadows on the retrieval of canopy and soil temperature data from four UAV images before and after applying shadow compensation techniques. The retrieved temperatures, using the TSEB-2T approach, both before and after shadow correction, are compared to the average temperature values for both soil and canopy in each grid. The imagery was acquired by the Utah State University AggieAir UAV system over a commercial vineyard located in California as part of the USDA Agricultural Research Service Grape Remote sensing Atmospheric Profile and Evapotranspiration Experiment (GRAPEX) Program during 2014 to 2016. The results of this study show when it is necessary to employ shadow compensation methods to retrieve vegetation and soil temperature directly.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31359902

RESUMO

Theoretically, the appearance of shadows in aerial imagery is not desirable for researchers because it leads to errors in object classification and bias in the calculation of indices. In contrast, shadows contain useful geometrical information about the objects blocking the light. Several studies have focused on estimation of building heights in urban areas using the length of shadows. This type of information can be used to predict the population of a region, water demand, etc., in urban areas. With the emergence of unmanned aerial vehicles (UAVs) and the availability of high- to super-high-resolution imagery, the important questions relating to shadows have received more attention. Three-dimensional imagery generated using UAV-based photogrammetric techniques can be very useful, particularly in agricultural applications such as in the development of an empirical equation between biomass or yield and the geometrical information of canopies or crops. However, evaluating the accuracy of the canopy or crop height requires labor-intensive efforts. In contrast, the geometrical relationship between the length of the shadows and the crop or canopy height can be inversely solved using the shadow length measured. In this study, object heights retrieved from UAV point clouds are validated using the geometrical shadow information retrieved from three sets of high-resolution imagery captured by Utah State University's AggieAir UAV system. These flights were conducted in 2014 and 2015 over a commercial vineyard located in California for the USDA Agricultural Research Service Grape Remote sensing Atmospheric Profile and Evapotranspiration Experiment (GRAPEX) Program. The results showed that, although this approach could be computationally expensive, it is faster than fieldwork and does not require an expensive and accurate instrument such as a real-time kinematic (RTK) GPS.

20.
Neth Heart J ; 27(6): 289-296, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31111456

RESUMO

The Editors' Network of the European Society of Cardiology (ESC) provides a dynamic forum for editorial discussions and endorses the recommendations of the International Committee of Medical Journal Editors (ICMJE) to improve the scientific quality of biomedical journals. Authorship confers credit and important academic rewards. Recently, however, the ICMJE emphasised that authorship also requires responsibility and accountability. These issues are now covered by the new (fourth) criterion for authorship. Authors should agree to be accountable and ensure that questions regarding the accuracy and integrity of the entire work will be appropriately addressed. This review discusses the implications of this paradigm shift on authorship requirements with the aim of increasing awareness of good scientific and editorial practices.

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