236 research outputs found
The role of stellar flares in planetary transits and exoatmospheres
No full textTreballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2024, Tutor: Octavi Fors AldrichAs the methods to characterize exoatmospheric components improve, the role played by stellar activity in the transmitted spectra is enhanced. Accurately detecting and modeling contributions like stellar flares is essential to remove their signals from the spectra. In this work, we analyze the light curves of TRAPPIST-1 b for the transits observed by the JWST NIRISS on 18 and 20 Jul 2022. A stellar flare during the transit has been found for 20 Jul using MCMC fitting and checking Hα emission. Our results indicate that, if not properly modeled and erased, flare contribution can mask and be misinterpreted as an atmospheric signal. The event found also has chemical implications, as the UV radiation emitted can induce certain chemical reactions.
Furthermore, depending on its characteristics, it can be fatal for complex living organisms. This study highlights the importance of accounting for stellar activity in exoplanet studies to avoid misdetections and better understand the star-planet interaction
The role of stellar flares in planetary transits and exoatmospheres
No full textTreballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2024, Tutor: Octavi Fors AldrichAs the methods to characterize exoatmospheric components improve, the role played by stellar activity in the transmitted spectra is enhanced. Accurately detecting and modeling contributions like stellar flares is essential to remove their signals from the spectra. In this work, we analyze the light curves of TRAPPIST-1 b for the transits observed by the JWST NIRISS on 18 and 20 Jul 2022. A stellar flare during the transit has been found for 20 Jul using MCMC fitting and checking Hα emission. Our results indicate that, if not properly modeled and erased, flare contribution can mask and be misinterpreted as an atmospheric signal. The event found also has chemical implications, as the UV radiation emitted can induce certain chemical reactions.
Furthermore, depending on its characteristics, it can be fatal for complex living organisms. This study highlights the importance of accounting for stellar activity in exoplanet studies to avoid misdetections and better understand the star-planet interaction
Searching for evidence of stellar cycles by using variations in flares rate
No full textTreballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2023, Tutor: Octavi Fors AldrichIn this work, evidence of stellar cycles is searched by analyzing variations in the rate of stellar flares. The focus is on two main sequence M-type stars plus an additional G-type target, all of them observed for 12-13 years by the Kepler and TESS missions. Each star’s data was detrended, and a flare detection method was applied. Then, in order to assess the existence of stellar cycles their cumulative Flare Frequency Distribution (FFD) was computed, as well as their fractional luminosity evolution. The typical distinct regions of a cumulative FFD, including the FFD’s turnoff point, were identified in the Kepler plots for all targets. On the TESS plots, such morphology was generally less apparent. The evolution of the fractional luminosity exhibited a decreasing trend of 0.4-0.5 decimal exponents throughout the entire timescale in those stars that showed evidence of activity cycles.
The validity of such evidence claims is also discusse
Multiresolution-based image fusion with additive wavelet decomposition
No full textThe standard data fusion methods may not be satisfactory to merge a high-resolution panchromatic image and a low-resolution multispectral image because they can distort the spectral characteristics of the multispectral data. The authors developed a technique, based on multiresolution wavelet decomposition, for the merging and data fusion of such images. The method presented consists of adding the wavelet coefficients of the high-resolution image to the multispectral (low-resolution) data. They have studied several possibilities concluding that the method which produces the best results consists in adding the high order coefficients of the wavelet transform of the panchromatic image to the intensity component (defined as L=(R+G+B)/3) of the multispectral image. The method is, thus, an improvement on standard intensity-hue-saturation (IHS or LHS) mergers. They used the ¿a trous¿ algorithm which allows the use of a dyadic wavelet to merge nondyadic data in a simple and efficient scheme. They used the method to merge SPOT and LANDSATTM images. The technique presented is clearly better than the IHS and LHS mergers in preserving both spectral and spatial information
Introduction of sensor spectral response into image fusion methods. Application to wavelet-based methods
No full textUsual image fusion methods inject features from a high spatial resolution panchromatic sensor into every low spatial resolution multispectral band trying to preserve spectral signatures and improve spatial resolution to that of the panchromatic sensor. The objective is to obtain the image that would be observed by a sensor with the same spectral response (i.e., spectral sensitivity and quantum efficiency) as the multispectral sensors and the spatial resolution of the panchromatic sensor. But in these methods, features from electromagnetic spectrum regions not covered by multispectral sensors are injected into them, and physical spectral responses of the sensors are not considered during this process. This produces some undesirable effects, such as resolution overinjection images and slightly modified spectral signatures in some features. The authors present a technique which takes into account the physical electromagnetic spectrum responses of sensors during the fusion process, which produces images closer to the image obtained by the ideal sensor than those obtained by usual wavelet-based image fusion methods. This technique is used to define a new wavelet-based image fusion method
Power Issues in Psychotherapy: Reflections on psychoanalytic theory and clinical cases
No full textThe dissertation examines power issues in psychotherapy from different angles of vision and integrates diverse perspectives on power; for example, professional power, transferential power, sociopolitical power, and bureaucratic power. Through topics of the medical record, the patient-therapist relationship, geographical space, minority issues in diagnosis, and clinical challenges involving third parties, I explore unconscious and preconscious power dynamics. The work aims to integrate, and make clinically accessible, some diverse and relatively abstruse writing on power as it may affect the treatment situation. The overarching conclusion of the dissertation is that addressing power in psychotherapy is a subtle, complex, and important ongoing process that has not been fully theorized. It is not a question that can be clarified once and for all. Nor is it a question that is fully separable from the therapist's own subjectivity, internalized norms, or social experiences with privileges and/or experiences of discrimination. The work is based in traditional literature studies (Jesson, Matheson & Lacey, 2011) and the case study method (Fishman & Messer, 2013; McLeod, 2011; Yin, 2012), in which the focus is on finding analytical and theoretical generalizations (Yin, 2012). In an attempt to make the work clinically relevant, I emphasize that even the most morally and cognitively sophisticated therapist (and patient) inevitably will have internalized elements of societal norms and prejudices, consciously or unconsciously (e.g., Davids, 2003; Layton, 2006b; Yancy, 2015).
In the first study (Fors & McWilliams, 2016), my co-author and I explore the undertheorized question of sharing patients’ medical records as part of the therapeutic process in mental health treatment. The intervention of collaborative reading of medical records is hence put in a therapeutic context and integrated with the goals and language of psychotherapy.
The second study (Fors, 2018b) is a theoretical paper, formulating urbanity as a seldom-addressed privilege and exploring implications of the misrepresentation or absence of the rural world on the “map” of psychotherapy. I “countermap” urban biases with respect to power, space, and time, and I explore some implications for therapeutic ethics, the frame, self-disclosure, and potential interpretation as I investigate the urban valuing of specialized expertise over wisdom, urban disconnection from weather and distance, urban colonizing behavior, the dumping of incompetent professionals into rural areas, and the urban sense of entitlement to anonymity.
The third study is a theoretical paper (Drescher & Fors, 2018) analyzing how minority issues are framed in the Psychodynamic Diagnostic Manual, 2nd ed. (PDM-2) (Lingiardi & McWilliams, 2017). I conclude that the PDM-2, despite giving greater attention to minority issues than other classification systems, gives no clinical guidance for issues that arise when a minority therapist treats a minority patient. I posit that distortions of envy, internalized subordination in both parties, countertransference, idealization, disappointment, and unspoken wishes to be understood by someone on whom sameness can be projected are characteristic of such dyads.
The fourth study (Fors, in press) is a theoretical paper in which four domains of power are highlighted. These areas include professional power, transferential power, socio-political power, and bureaucratic power, all of which are explored through the case of “Sonja.”
The fifth study (Fors, 2020b) is a theoretical contribution suggesting a conceptual model of how relative power in psychotherapy might be framed. I offer an integrative model, the matrix of relative privilege, as a useful tool for exploring how social power is ongoingly negotiated in clinical dyads. It potentially brings social justice concerns into the technical sphere, not simply the ethical sensibility, of the consulting room
A wavelet-based method for the determination of the relative resolution between remotely sensed images
No full textSpatial resolution is a key parameter of all remote sensing satellites and platforms. The nominal spatial resolution of satellites is a well-known characteristic because it is directly related to the area in ground that represents a pixel in the detector. Nevertheless, in practice, the actual resolution of a specific image obtained from a satellite is difficult to know precisely because it depends on many other factors such as atmospheric conditions. However, if one has two or more images of the same region, it is possible to compare their relative resolutions. In this paper, a wavelet-decomposition-based method for the determination of the relative resolution between two remotely sensed images of the same area is proposed. The method can be applied to panchromatic, multispectral, and mixed (one panchromatic and one multispectral) images. As an example, the method was applied to compute the relative resolution between SPOT-3, Landsat-5, and Landsat-7 panchromatic and multispectral images taken under similar as well as under very different conditions. On the other hand, if the true absolute resolution of one of the images of the pair is known, the resolution of the other can be computed. Thus, in the last part of this paper, a spatial calibrator that is designed and constructed to help compute the absolute resolution of a single remotely sensed image is described, and an example of its use is presented
Integración del archivo de imágenes de un telescopio robótico al observatorio virtual
No full textAquest document conté originàriament altre material i/o programari només consultable a la Biblioteca de Ciència i Tecnologia.S'ha implementat un servei VO (Virtual Observatori) a les instal lacions del Telescopi TFRM, que permet distribuir les imatges preses amb el telescopi de manera remota i automàtica a qualsevol usuari del servei. El servei està format per un arxiu d'imatges, una aplicació que integra les imatges a l'arxiu y una aplicació que es comunica amb els clients d'VO, rebent peticions i responen segons s'especifica al protocol SIAP (Simple Image Access Protocol).Se ha implementado un servicio de Observatorio Virtual (VO) en las instalaciones del telescopio TFRM, que permite distribuir las imágenes tomadas por el telescopio de una forma remota y automática a cualquier usuario del servicio. El servicio esta formado por un archivo de imágenes, una aplicación que integra las imágenes en el archivo y una aplicación que se comunica con los clientes de IVOA, recibiendo peticiones y respondiendo según se especifica en el protocolo SIAP (Simple Image Access Protocol).We have implemented a Virtual Observatory (VO) service at Telescope Facility in TFRM, which allows distributing the images taken by the telescope in a remote and automatic way to any service user. The service consists of an image archive, an application that integrate images on file and an application that communicates with VO clients, receiving and answering requests as specified in SIAP protocol (Simple Image Access Protocol)
Virtual patients design and its effect on clinical reasoning and student experience : a protocol for a randomised factorial multi-centre study
No full textBackground
Virtual Patients (VPs) are web-based representations of realistic clinical cases. They are proposed as being an optimal method for teaching clinical reasoning skills. International standards exist which define precisely what constitutes a VP. There are multiple design possibilities for VPs, however there is little formal evidence to support individual design features. The purpose of this trial is to explore the effect of two different potentially important design features on clinical reasoning skills and the student experience. These are the branching case pathways (present or absent) and structured clinical reasoning feedback (present or absent).
Methods/Design
This is a multi-centre randomised 2x2 factorial design study evaluating two independent variables of VP design, branching (present or absent), and structured clinical reasoning feedback (present or absent).The study will be carried out in medical student volunteers in one year group from three university medical schools in the United Kingdom, Warwick, Keele and Birmingham. There are four core musculoskeletal topics. Each case can be designed in four different ways, equating to 16 VPs required for the research. Students will be randomised to four groups, completing the four VP topics in the same order, but with each group exposed to a different VP design sequentially. All students will be exposed to the four designs. Primary outcomes are performance for each case design in a standardized fifteen item clinical reasoning assessment, integrated into each VP, which is identical for each topic. Additionally a 15-item self-reported evaluation is completed for each VP, based on a widely used EViP tool. Student patterns of use of the VPs will be recorded.
In one centre, formative clinical and examination performance will be recorded, along with a self reported pre and post-intervention reasoning score, the DTI. Our power calculations indicate a sample size of 112 is required for both primary outcomes
How do people perceive urban trees? Assessing likes and dislikes in relation to the trees of a city
No full textabstract: Cities are systems that include natural and human-created components. When a city grows without proper planning, it tends to have low environmental quality. If improving environmental quality is intended, people’s opinion should be taken into account for a better acceptance of urban management decisions. In this study, we assessed people’s perception of trees by conducting a survey with a controlled sample of citizens from the city of Morelia (west-central Mexico). Citizens liked both native and exotic tree species and rejected mainly exotic ones. Preference for trees were related to tree attributes; such as size. Trees that dropped leaves or tended to fall were not liked. The most-mentioned tree-related benefits were oxygen supply and shade; the most mentioned tree-related damages were accidents and infrastructure damage. The majority of respondents preferred trees near houses to increase tree density. Also, most respondents preferred trees in green areas as well as close to their houses, as they consider that trees provide oxygen. The majority of the respondents thought more trees were needed in the city. In general, our results show that although people perceive that trees in urban areas can cause damages, they often show more interest for the benefits related to trees and consider there should be more trees in cities. We strongly suggest the development of studies that broaden our knowledge of citizen preferences in relation to urban vegetation, and that further policy making takes their perception into account when considering creating new urban green areas, regardless of their type or size.Corresponding Author:
Ian MacGregor-Fors
Red de Ambiente y Sustentabilidad, Instituto de EcologíaXalapaMexico
[email protected]
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