Aims.
Both components of the bright eclipsing binary
α
Dra have been resolved using long baseline interferometry and the secondary component has been shown to contribute approximately 15% of the ...total flux; however, a spectroscopic detection of the companion star has so far been unsuccessful. We aim for a firm spectroscopic detection of the secondary component of
α
Dra using state-of-the-art spectroscopic analysis methods for very high-quality spectroscopic observations. This will allow the determination of fundamental and atmospheric properties of the components in the system with high precision and accuracy.
Methods.
To achieve our goals, we use a combined data set from interferometry with the Navy Precision Optical Interferometer (NPOI), photometry with the TESS space observatory, and high-resolution spectroscopy with the H
ERMES
fibre-fed spectrograph at the La Palma observatory. We use the method of spectral disentangling to search for the contribution of a companion star in the observed composite H
ERMES
spectra, to separate the spectral contributions of both components, and to determine orbital elements of the
α
Dra system. TESS light curves are analysed in an iterative fashion with spectroscopic inference of stellar atmospheric parameters to determine fundamental stellar properties and their uncertainties. Finally, NPOI interferometric measurements are used for determination of the orbital parameters of the system and angular diameters of both binary components.
Results.
We report the first firm spectroscopic detection of the secondary component in
α
Dra and deliver disentangled spectra of both binary components. The components’ masses and radii are inferred with high precision and accuracy, and are
M
A
= 3.186 ± 0.044
M
⊙
,
R
A
= 4.932 ± 0.036
R
⊙
, and
M
B
= 2.431 ± 0.019
M
⊙
,
R
B
= 2.326 ± 0.052
R
⊙
for the primary and secondary components, respectively. Combined astrometric and spectroscopic analysis yields the semi-major axis of the system, which is ultimately used to derive the dynamical parallax of
π
= 11.48 ± 0.13 mas, and the distance
d
= 87.07 ± 1.03 pc to the
α
Dra system. Evolutionary analysis of both binary components with M
ESA
stellar structure and evolution models suggests the primary is an evolved post-TAMS A-type star, while the companion is a main-sequence A-type star with a convective core mass of
M
cc
= 0.337 ± 0.011
M
⊙
. Positions of both binary components in the Kiel- and HR-diagrams suggest a value of the convective core overshooting parameter
f
ov
well below 0.010
H
p
, and we infer the age of the system to be 310 ± 25 Myr.
Conclusions.
The inferred near-core mixing properties of both components do not support a dependence of the convective core overshooting on the stellar mass. At the same time, the
α
Dra system provides extra support to hypothesise that the mass discrepancy in eclipsing spectroscopic double-lined binaries is associated with inferior atmospheric modelling of intermediate- and high-mass stars, and less so with the predictive powerof stellar structure and evolution models as to the amount of near-core mixing and mass of the convective core.
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Abridged. Eclipsing spectroscopic double-lined binaries are the prime source of precise and accurate measurements of masses and radii of stars. These measurements provide a stringent test of models ...of stellar evolution that are persistently reported to contain major shortcomings. The mass discrepancy observed for the eclipsing spectroscopic double-lined binaries is one of the manifestations of shortcomings in stellar evolution models. Our ultimate goal is to provide an observational mapping of the mass discrepancy and propose a recipe for its solution. We initiate a spectroscopic monitoring campaign of 573 candidate eclipsing binaries of which 83 are analysed in this work with the methods of least-squares deconvolution and spectral disentangling. TESS light curves are used to provide photometric classification of the systems according to the type of their intrinsic variability. We confirm 69 systems as either spectroscopic binaries or higher-order multiple systems. Twelve stars are classified as single and two more objects are found at the interface of their line profile variability being interpreted as due to binarity and intrinsic variability of the star. Moreover, 20 eclipsing binaries are found to contain at least one component that exhibits stellar oscillations. The sample presented in this work contains both detached and semi-detached systems and covers a range in the effective temperature and mass of the star of Teff = 7000,30000 K and M = 1.5,15 M_Sun, respectively. We conclude an appreciable capability of the spectral disentangling method to deliver precise and accurate spectroscopic orbital elements from as few as 6-8 orbital phase-resolved spectroscopic observations. Orbital solutions obtained this way are accurate enough to deliver age estimates with accuracy of 10% or better, an important resource for calibration of stellar evolution models.
Altough both components of the bright eclipsing binary \(\alpha\) Dra having been resolved using long baseline interferometry and the secondary component shown to contribute some 15\% of the total ...flux, a spectroscopic detection of the companion star was so far unsuccessful. To achieve our goals, we use a combined data set from interferometry with the Navy Precision Optical Interferometer (NPOI), photometry with the TESS space observatory, and high-resolution spectroscopy with the HERMES fibre-fed spectrograph at the La Palma observatory. We use the method of spectral disentangling to search for the contribution of a companion star in the observed composite HERMES spectra, to separate the spectral contributions of both components, and to determine orbital elements of the \(\alpha\) Dra system. TESS light curves are analysed in an iterative fashion with spectroscopic inference of stellar atmospheric parameters to determine fundamental stellar properties and their uncertainties. Finally, NPOI interferometric measurements are used for determination of the orbital parameters of the system and angular diameters of both binary components. We report the first firm spectroscopic detection of the secondary component in \(\alpha\) Dra and deliver disentangled spectra of both binary components. The inferred near-core mixing properties of both components do not support a dependence of the convective core overshooting on the stellar mass. At the same time, the \(\alpha\) Dra system provides extra support to hypothesise that the mass discrepancy in eclipsing spectroscopic double-lined binaries is associated with inferior atmospheric modelling of intermediate- and high-mass stars, and less so with the predictive power of stellar structure and evolution models as to the amount of near-core mixing and mass of the convective core. (abridged abstract)
The article presents the optical and spectral facets of the notion of intersectionality in their materiality, in their forms as bodies and ghosts, doors, and thresholds. Scholarship on ...intersectionality has focused on critiquing the legal assumption that considers categories of discrimination to correspond to discrete aspects of identity, due to its negative effect of rendering certain experiences unrepresentable. As a consequence, the optical approach seeks to expose intersections and to reveal what remains hidden under these discrete frames. I would like to take the opportunity to write about Goodrich’s law, to delve into an additional register that is underdeveloped but, I argue, contained in the legal concept of intersectionality. Intersectionality has not addressed the spectral, the search for becoming, or the intent to conceptualize an encounter without anticipation, announcement, or previsions, even if that implies defying what a concept entails. Both are inextricably connected. Here I will distinguish the optical and the spectral aspects of the theory. The optical or operational side of intersectionality offers a door while the specter that phantasmatically sustains and holds intersectionality’s impulse in legal practice allows the manifestation of the illegible within the legible.
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The paper focuses on the way human rights law has been incorporating notions of intersectionality through legal instruments as well as through human rights courts’ decisions. The overall goal is to ...expose the shortcomings of the current conception of intersectionality as it has been applied by the Inter-American Court, which, I argue, derive from a categorical understanding of group and identity-based rights transplanted from the notion of structural discrimination. The paper argues that approaching human rights violations by means of categorical reasoning is detrimental to intersectional interests, since it perpetuates the problem that intersectionality seeks to overcome in the first place, and suggests that cutting across categories is a potentially more fruitful pathway for the future of intersectionality in the legal field.
When I first decided to investigate an intersectional approach to frame forces operating in cases of indigenous women affected by land conflicts, I had not envisioned that the metaphorical aspect ...would be such a crucial part of operationalizing the concept. Since its first formulation, the term intersectionality has been attached to the image of intersecting roads, and still today when searching for online videos for pedagogical purposes, the results show cars driving towards people standing on crossroads to explain the meaning. Intersecting roads, however, also emerged in my fieldwork in a literal maner. The passage from metaphor to materiality of the concept of intersectionality, I argue, can affect the identitarian logic that predominates in most proclaimed legal intersectional approaches. The paper proposes to bring intersectionality to materiality by re-imagining the metaphor of intersectionality through an ethnographic approach to indigenous peoples' land conflicts in La Pampa, Argentina.
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Intersectionality has been praised as the most important contribution that gender studies has achieved so far (McCall, 2005, p. 1771), as a result of its promising ambition to allow for more ...effective ways of addressing the many and complex forms of oppression that women experience (Conaghan, 2009, p. 21). At the same time, intersectionality has raised heated debates around its origin, methodologies, its relationship with identity politics and legal implications, among other disputes (Nash, 2017, p. 118). This paper has the main purpose of bringing an initial approach to the concept of intersectionality from three different dimensions: theory, law and practice. The first section will explain theoretical developments of intersectionality that will allow to introduce the main challenges the concept faces. The second section will explore how the concept was received within the legal field, and will be compared to the principle of non-discrimination, specifically in the human rights field. The third section, will analyze how theoretical and normative aspects of intersectionality were actually applied in recent decisions of the Inter- American Court on Human Rights.
Abstract Gebruers N, Vanroy C, Truijen S, Engelborghs S, De Deyn PP. Monitoring of physical activity after stroke: a systematic review of accelerometry-based measures. Objective To assess the ...clinimetric properties and clinical applicability of different accelerometry-based measurement techniques in persons with stroke. Data Sources A systematic search of literature was performed using a specific search strategy by means of different electronic databases until October 2008 (PubMed, EMBASE, CINAHL, Cochrane Library of Clinical Trials). Study Selection A first selection was made by means of title and abstract. A second selection was performed by means of predefined inclusion criteria: (1) accelerometry in stroke population, (2) application of accelerometry in patients with stroke including clinimetric properties. The exclusion criteria were (1) dysphagia, (2) new engineering techniques or software alterations, (3) secondary sources, and (4) Case studies. Data Extraction The clinimetric properties and applicability of accelerometry were described based on the included publications. Data Synthesis Twenty-five articles (4 randomized controlled trials) were included. The information of the publications was divided into (1) gait, cadence, and ambulatory activity; (2) upper-extremity activity; and (3) topics related to stroke other than upper or lower extremity. Accelerometry was shown to be valid and had good test-retest reliability in a large number of settings. Numerous studies demonstrated correlations between accelerometry and common stroke scales. Trunk movements were measured as an outcome of disturbed gait. The vertical asymmetry index especially was able to differentiate between persons with stroke and healthy controls. Persons with stroke showed less ambulatory activity, measured as steps per day, than sedentary controls. Triaxial accelerometry was able to distinguish between varying activity levels. Upper-extremity use was lesser in persons with stroke. It was impossible to calculate a minimal clinical difference for arm use by a uniaxial accelerometer. Evidence was presented that finger-tapping and sit-to-stand measured by accelerometers could be used to define recovery from stroke. Conclusions The literature concerning accelerometry incorporated into stroke research is young, limiting the ability to draw consistent conclusions. Nonetheless, the available evidence suggests that accelerometers yield valid and reliable data about the physical activity of patients with stroke. Future research is necessary to investigate clinimetric properties like predictive value and responsiveness further before implementing accelerometry in clinical trials as an outcome for change.
The aim of the present study was to evaluate the effects of compression bandages, sleeves, intermittent pneumatic compression (IPC) and active exercise on the reduction of breast cancer-related ...lymphoedema (BCRL). A systematic literature search up to the year January 2016 was performed in CINAHL, Cochrane Register of Controlled Trials, Embase, International Clinical Trials Registry Platform (WHO), PEDro and PubMed. Inclusion criteria were (1) RCTs, (2) reported adequate statistics for meta-analysis, (3) English or German language. Exclusion criteria were (1) effects of drugs, hormonal, radiation and surgical procedures, (2) studies with children, (3) non-breast cancers, lower extremity oedema, (4) impact on fatigue only, diets or sexually transmitted diseases, (5) cost-analysis only and (6) non-carcinogenic syndromes or (7) prevention of breast cancer. After scoring the methodological quality of the selected studies, data concerning volume reduction of the oedema swelling were extracted. Thirty-two studies were included in this systematic review. Nine studies were selected for the RCT-based studies and 19 studies were included in the pre–post studies-based random-effects meta-analyses. All conclusions should be taken with precautions because of the insufficient quality of the selected papers. Exercise seems beneficial in reducing oedema volume in BCRL. IPC seems beneficial in helping to reduce the oedema volume in the acute phase of treatment. Compression sleeves do not aid in the volume reduction in the acute phase; however, they do prevent additional swelling.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Objectives
To provide an overview of costs associated with the treatment of breast cancer-related lymphoedema (BCRL) and its possible sequelae, borne by patients or by society.
Data sources
According ...to the PRISMA guideline, a systematic literature search was carried out in four electronic databases: PubMed, Web of Science, Cochrane Clinical Trials and EMBASE. Searches were performed on October 1, 2018.
Study selection
Eligibility criteria: (1) expenses of adults (age > 18 years), (2) concerning patients with BCRL, (3) overview of (in)direct costs associated with BCRL, (4) expenses in which at least one type of conservative treatment modality for lymphoedema is included and/or costs for hospital admissions due to infections. Reviews and meta-analyses were excluded.
Data extraction
After assessing the risk of bias and level of evidence, quantitative data on (in)direct costs for BCRL treatment during a well-mentioned timeframe were extracted.
Data synthesis
Eight studies were included. Three studies reported on patient-borne costs related to BCRL. Mean direct costs per year borne by patients ranged between USD$2306 and USD$2574. Indirect costs borne by patients ranged between USD$3325 and USD$5545 per year. Five studies estimated society-borne costs related to BCRL from claims data, billing prices and providers’ services during 12 to 24 months of follow-up. Mean direct treatment costs after 1 year of decongestive lymphatic therapy (DLT) ranged between €799 (= USD$1126.60) and USD$3165.
Conclusion
This systematic review revealed that BCRL imposes a substantial economic burden on patients and society. However, more standardized high-quality health economic analyses among this field are required. Recent economic analyses related to BCRL treatment in Europe, Asia, Africa and South America are lacking. Worldwide, further scrutiny of the economic impact of DLT for BCRL in clinical settings is needed.
Clinical trial registration number
The review makes part of a double-blind, multi-center, randomized controlled trial (EFforT-BCRL trial), which is registered in clinicaltrials.gov (NCT02609724). CME reference S58689, EudraCT Number 2015-004822-33.
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