231 research outputs found

    C2_2H observations toward the Orion Bar

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    C2_2H is one of the first radicals to be detected in the interstellar medium. Its higher rotational transitions have recently become available with the Herschel Space Observatory. We aim to constrain the physical parameters of the C2_2H emitting gas toward the Orion Bar. We analyse the C2_2H line intensities measured toward the Orion Bar CO+^+ Peak and Herschel/HIFI maps of C2_2H, CH, and HCO+^+, and a NANTEN map of [CI]. We interpret the observed C2_2H emission using radiative transfer and PDR models. Five rotational transitions of C2_2H have been detected in the HIFI frequency range toward the CO+^+ peak. A single component rotational diagram gives a rotation temperature of ~64 K and a beam-averaged C2_2H column density of 4×\times1013^{13} cm2^{-2}. The measured transitions cannot be explained by any single parameter model. According to a non-LTE model, most of the C2_2H column density produces the lower-NN C2_2H transitions and traces a warm (TkinT_{\rm{kin}} ~ 100-150 K) and dense (nn(H2_2)~105^5-106^6 cm3^{-3}) gas. A small fraction of the C2_2H column density is required to reproduce the intensity of the highest-NN transitions (NN=9-8 and N=10-9) originating from a high density (nn(H2_2)~5×\times106^6 cm3^{-3}) hot (TkinT_{\rm{kin}} ~ 400 K) gas. The total beam-averaged C2_2H column density in the model is 1014^{14} cm2^{-2}. Both the non-LTE radiative transfer model and a simple PDR model representing the Orion Bar with a plane-parallel slab of gas and dust suggest, that C2_2H cannot be described by a single pressure component, unlike the reactive ion CH+^+, which was previously analysed toward the Orion Bar CO+^+ peak. The physical parameters traced by the higher rotational transitions (NN=6-5,...,10-9) of C2_2H may be consistent with the edges of dense clumps exposed to UV radiation near the ionization front of the Orion Bar.Comment: Proposed for acceptance in A&A, abstract abridge

    A Flexible and Efficient Temporal Logic Tool for Python: PyTeLo

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    Temporal logic is an important tool for specifying complex behaviors of systems. It can be used to define properties for verification and monitoring, as well as goals for synthesis tools, allowing users to specify rich missions and tasks. Some of the most popular temporal logics include Metric Temporal Logic (MTL), Signal Temporal Logic (STL), and weighted STL (wSTL), which also allow the definition of timing constraints. In this work, we introduce PyTeLo, a modular and versatile Python-based software that facilitates working with temporal logic languages, specifically MTL, STL, and wSTL. Applying PyTeLo requires only a string representation of the temporal logic specification and, optionally, the dynamics of the system of interest. Next, PyTeLo reads the specification using an ANTLR-generated parser and generates an Abstract Syntax Tree (AST) that captures the structure of the formula. For synthesis, the AST serves to recursively encode the specification into a Mixed Integer Linear Program (MILP) that is solved using a commercial solver such as Gurobi. We describe the architecture and capabilities of PyTeLo and provide example applications highlighting its adaptability and extensibility for various research problems

    Risks and risk mitigation in waste-work: A qualitative study of informal waste workers in Nepal

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    Objectives To explore how informal waste workers (IWWs) working in Kathmandu Valley perceive risks associated with waste work and what they do to mitigate them. Study design Qualitative Study Design. Methods A mix of one-to-one semi-structured interviews (n ​= ​18) and focus group discussions (n ​= ​4) with IWWs were undertaken. Participants were recruited purposively using snowball sampling. All interviews and discussions were audio-recorded, transcribed verbatim, translated and subsequently analysed thematically. Results The IWWs perceived discrimination and health risks as the main risks associated with waste work. IWWs reported considerable stigma and discrimination not only from the wider society but also from family members and within their own profession. Similarly, the occupational risks most frequently recognized were physical injuries and cuts from working with waste. However, the potential risks from hazardous chemicals present in or generated from waste were not articulated by participants. Mitigation strategies to combat the risks included avoidance, greater care and the use of informal means of “protection”. Awareness of the importance of personal protective equipment (PPE) was limited. The key barriers to the use of PPE identified included costs, the lack of easy availability of PPE and the inconvenience of working with PPE. Conclusions The vulnerability of informal waste workers in Nepal is multifaceted. A range of policy and regulatory measures, along with interventions that promote greater social inclusion and occupational support are needed to promote IWW’s health and safety

    Fluorescence kinetics of flavin adenine dinucleotide in different microenvironments

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    Fluorescence kinetics of flavin adenine dinucleotide was measured in a wide time and spectral range in different media, affecting its intra- end extramolecular interactions, and analyzed by a new method based on compressed sensing

    Geometric characterization of nodal domains: the area-to-perimeter ratio

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    In an attempt to characterize the distribution of forms and shapes of nodal domains in wave functions, we define a geometric parameter - the ratio ρ\rho between the area of a domain and its perimeter, measured in units of the wavelength 1/E1/\sqrt{E}. We show that the distribution function P(ρ)P(\rho) can distinguish between domains in which the classical dynamics is regular or chaotic. For separable surfaces, we compute the limiting distribution, and show that it is supported by an interval, which is independent of the properties of the surface. In systems which are chaotic, or in random-waves, the area-to-perimeter distribution has substantially different features which we study numerically. We compare the features of the distribution for chaotic wave functions with the predictions of the percolation model to find agreement, but only for nodal domains which are big with respect to the wavelength scale. This work is also closely related to, and provides a new point of view on isoperimetric inequalities.Comment: 22 pages, 11 figure

    Dutch translation and cross-cultural validation of the Adult Social Care Outcomes Toolkit (ASCOT)

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    Background: The Adult Social Care Outcomes Toolkit was developed to measure outcomes of social care in England. In this study, we translated the four level self-completion version (SCT-4) of the ASCOT for use in the Netherlands and performed a cross-cultural validation. Methods: The ASCOT SCT-4 was translated into Dutch following international guidelines, including two forward and back translations. The resulting version was pilot tested among frail older adults using think-aloud interviews. Furthermore, using a subsample of the Dutch ACT-study, we investigated test-retest reliability and construct validity and compared response distributions with data from a comparable English study. Results: The pilot tests showed that translated items were in general understood as intended, that most items were reliable, and that the response distributions of the Dutch translation and associations with other measures were comparable to the original English version. Based on the results of the pilot tests, some small modifications and a revision of the Dignity items were proposed for the final translation, which were approved by the ASCOT development team. The complete original English version and the final Dutch translation can be obtained after registration on the ASCOT website (http://www.pssru.ac.uk/ascot). Conclusions: This study provides preliminary evidence that the Dutch translation of the ASCOT is valid, reliable and comparable to the original English version. We recommend further research to confirm the validity of the modified Dutch ASCOT translation

    Validation of the Spanish Version of the ICECAP-O for Nursing Home Residents with Dementia

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    Background Measurement of health-related quality of life (HRQoL) is important for a chronic disease, such as dementia, which impairs the quality of life of affected patients in addition to their length of life. This is important in the context of economic evaluations when interventions do not (only) affect HRQoL and these other factors also affect overall quality of life. Objective To validate the Spanish translation of the ICECAP-O's capability to measure Health-related quality of life in elderly with dementia who live in nursing homes. Method Cross-sectional study. For 217 residents living in 8 Spanish nursing homes, questionnaires were completed by nursing professionals serving as proxy respondents. We analyzed the internal consistency and other psychometric properties. We investigated the convergent validity of the ICECAP-O with other HRQoL instruments, the EQ-5D extended with a cognitive dimension (EQ-5D+C), the Alzheimer's Disease Related Quality of Life (ADRQL) measures, and the Barthel Index measure of activities of daily living (ADL). Results The ICECAP-O presents satisfactory internal consistency (alpha 0.820). The factorial analysis indicated a structure of five principal dimensions that explain 66.57% of the total variance. Convergent validity between the ICECAP-O, EQ-5D+C, ADRQL, and Barthel Index scores was moderate to good (with correlations of 0.62, 0.61, and 0.68, respectively), but differed between dimensions of the instruments. Discriminant validity was confirmed by finding differences in ICECAP-O scores between subgroups based on ADL scores (0.70 low, 0.59 medium, and 0.39 high level care), dementia severity (0.72 mild, 0.63 medium, and 0.50 severe), and ages (0.59 below 75 years and 0.84 above 75 years). Conclusions This study presented the first use of a Spanish version of the ICECAP-O. The results indicate that the ICECAP-O appears to be a reliable Health-related quality of life measurement instrument showing good convergent and discriminant validity for people with dementia

    Establishing a composite endpoint for measuring the effectiveness of geriatric interventions based on older persons' and informal caregivers' preference weights:a vignette study

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    Background: The Older Persons and Informal Caregivers Survey Minimal Dataset's (TOPICS-MDS) questionnaire which measures relevant outcomes for elderly people was successfully incorporated into over 60 research projects of the Dutch National Care for the Elderly Programme. A composite endpoint (CEP) for this instrument would be helpful to compare effectiveness of the various intervention projects. Therefore, our aim is to establish a CEP for the TOPICS-MDS questionnaire, based on the preferences of elderly persons and informal caregivers. Methods: A vignette study was conducted with 200 persons (124 elderly and 76 informal caregivers) as raters. The vignettes described eight TOPICS-MDS outcomes of older persons (morbidity, functional limitations, emotional wellbeing, pain experience, cognitive functioning, social functioning, self-perceived health and self-perceived quality of life) and the raters assessed the general well-being (GWB) of these vignette cases on a numeric rating scale (0-10). Mixed linear regression analyses were used to derive the preference weights of the TOPICS-MDS outcomes (dependent variable: GWB scores; fixed factors: the eight outcomes; unstandardized coefficients: preference weights). Results: The mixed regression model that combined the eight outcomes showed that the weights varied from 0.01 for social functioning to 0.16 for self-perceived health. A model that included "informal caregiver" showed that the interactions between this variable and each of the eight outcomes were not significant (p > 0.05). Conclusion: A preference-weighted CEP for TOPICS-MDS questionnaire was established based on the preferences of older persons and informal caregivers. With this CEP optimal comparing the effectiveness of interventions in older persons can be realized
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