6,121 research outputs found
The horizontal resolution of MIPAS
Limb remote sensing from space provides atmospheric composition measurements at high vertical resolution while the information is smeared in the horizontal domain. The horizontal components of two-dimensional (altitude and along-track coordinate) averaging kernels of a limb retrieval constrained to horizontal homogeneity can be used to estimate the horizontal resolution of limb retrievals. This is useful for comparisons of measured data with modeled data, to construct horizontal observation operators in data assimilation applications or when measurements of different horizontal resolution are intercompared. We present these averaging kernels for retrievals of temperature, H2O, O3, CH4, N2O, HNO3 and NO2 from MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) high-resolution limb emission spectra. The horizontal smearing of a MIPAS retrieval in terms of full width at half maximum of the rows of the horizontal averaging kernel matrix varies typically between about 200 and 350 km for most species, altitudes and atmospheric conditions. The range where 95% of the information originates from varies from about 260 to 440 km for these cases. This information spread is smaller than the MIPAS horizontal sampling, i.e. MIPAS data are horizontally undersampled, and the effective horizontal resolution is driven by the sampling rather than the smearing. The point where the majority of the information originates from is displaced from the tangent point towards the satellite by typically less than 10 km for trace gas profiles and about 50 to 100 km for temperature, with a few exceptions for uppermost altitudes. The geolocation of a MIPAS profile is defined as the tangent point of the middle line of sight in a MIPAS limb scan. The majority of the information displacement with respect to this nominal geolocation of the measurement is caused by the satellite movement and the geometrical displacement of the actual tangent point as a function of the elevation angle
Total evaporation estimates from a Renosterveld and dryland wheat/fallow surface at the Voëlvlei Nature Reserve (South Africa)
Accurate quantification of the water balance, in particular evapotranspiration, is fundamental in managing water resources, especially in semi-arid areas. The objective of this study was to compare evaporation from endemic vegetation – Renosterveld – and a dryland wheat/fallow cropping system. The study was carried out in the mid-reaches of the Berg River catchment (South Africa), characterised by dryland salinity. Measurements of total evaporation from these 2 land uses were carried out with large aperture scintillometers during window periods from 2005 to 2007. Total evaporation was measured to be higher in Renosterveld than in wheat during the rainy winter season. In the dry summer season, total evaporation from Renosterveld was limited by soil water supply, and vegetation was under water stress. Spatial variability of total evaporation from both wheat/fallow land and Renosterveld was estimated using the Surface Energy Balance Algorithm for Land (SEBAL) model for 3 climatically different years. The scintillometer measurements were used to determine basal crop coefficients for long-term (20 years) simulations with the HYDRUS-1D model to assess temporal variability in total evaporation. Long-term simulations indicated that well-established, deep-rooted Renosterveld uses 39% more water than the shallowrooted wheat/fallow system. A change in land use from Renosterveld to dryland annual crops could therefore affect the soil water balance, cause shallow saline groundwater tables and degradation of soil and water resources.Keywords: evapotranspiration; large aperture scintillometer; Renosterveld; soil water balance; Surface Energy Balance Algorithm for Land (SEBAL); wheat/fallow syste
Time-dependent Hamiltonian estimation for Doppler velocimetry of trapped ions
The time evolution of a closed quantum system is connected to its Hamiltonian
through Schroedinger's equation. The ability to estimate the Hamiltonian is
critical to our understanding of quantum systems, and allows optimization of
control. Though spectroscopic methods allow time-independent Hamiltonians to be
recovered, for time-dependent Hamiltonians this task is more challenging. Here,
using a single trapped ion, we experimentally demonstrate a method for
estimating a time-dependent Hamiltonian of a single qubit. The method involves
measuring the time evolution of the qubit in a fixed basis as a function of a
time-independent offset term added to the Hamiltonian. In our system the
initially unknown Hamiltonian arises from transporting an ion through a static,
near-resonant laser beam. Hamiltonian estimation allows us to estimate the
spatial dependence of the laser beam intensity and the ion's velocity as a
function of time. This work is of direct value in optimizing transport
operations and transport-based gates in scalable trapped ion quantum
information processing, while the estimation technique is general enough that
it can be applied to other quantum systems, aiding the pursuit of high
operational fidelities in quantum control.Comment: 10 pages, 8 figure
Experiences in the development of electronic care plans for the management of comorbidities
Recent studies have shown that care plans with comprehen- sive home interventions can be effective in the management of chronic patients. Evidence also exists about the importance of tailoring these care plans to patients, by integrating comorbidities. In this context, the de- velopment, implementation, outcome analysis, and reengineering of care plans adapted to particular patient groups earn relevance. We are con- cerned with the development and reengineering of electronic care plans dealing with comorbidities. Our hypothesis is that a library of reusable care plan components can facilitate these tasks. To confirm this hypoth- esis we have carried out an experiment consisting in developing a library of care plan components for the management of patients with COPD3 or CHF4, and next building a care plan for stable COPD&CHF patients by (re)using these components. In this paper we report on this experimen
The relation between normative rituals/routines and obsessive-compulsive symptoms at a young age:A systematic review
Objective One of the most challenging issues in the pediatric obsessive–compulsive (OC) disorder field is to differentiate pathological OC symptoms from the phenotypically similar normative rituals/routines that characterize normal childhood development. Given their similarities, it can be questioned whether both constructs reflect two qualitatively distinct behavioral expressions of different etiological factors or rather reflect two diverse manifestations of one single continuum (cfr. the continuity hypothesis). Method This paper aims to improve our understanding of the relation between normative childhood rituals/routines and OC symptoms in two ways. First, the continuity hypothesis was investigated by systematically reviewing current evidence on this association, using various databases (Web of Science Core Collection, MEDLINE/PubMed, and SciELO Citation Index) from 1950 until February 1, 2019 (registration number: CRD42019121293). Second, based on this systematic review, an integrative conceptual model was developed describing this relation from different perspectives on sources of influence. Results The literature search initially revealed 2122 hits, with 114 full-texts being assessed for eligibility. After applying several selection criteria, 18 studies were included in the review. The results generally support the continuity hypothesis and reveal important etiological factors at different levels of behavioral analysis, including the phenotypic (anxiety), neurobiological and genetic level. Also age and the presence of other disorders appeared to be important factors in evaluating the level of normality. Conclusion We provide a conceptual framework to inform future research aimed at improving the understanding of the relationship between normative rituals/routines and pathological OC symptoms. Conceptual implications are discussed and clinical recommendations are given to improve early identification and differentiation
Isothiazole derivatives as antiviral agents
We recently described the synthesis and antiviral activity of the compounds 5-phenyl-3-(4-cyano-5-phenylisothiazol-3-yl) disulphanyl-4-isothiazole-carbonitrile and S-(4-cyano-5-phenylisothiazol-3-yl)- O-ethyl thiocarbonate, which were found to be effective against both HIV-1 (IIIB) and HIV-2 (ROD). We have now evaluated these compounds against both RNA and DNA viruses, obtaining high selectivity indexes for poliovirus 1 (SI: 223 and 828, respectively) and Echovirus 9 (SI: 334 and 200, respectively). In our previous studies, 3-methylthio-5-(4- OBn-phenyl)-4-isothiazolecarbo-nitrile was found to exhibit a broad spectrum of action against picornaviruses, we therefore selected this compound and S-(4-cyano-5-phenylisothiazol-3-yl)- O-ethyl thiocarbonate as the model for the synthesis of a new isothiazole derivative, S-[4-cyano-5-(4- OBn-phenyl)isothiazol-3-yl]- O-ethyl thiocarbonate. This compound was evaluated against picornaviruses, measles virus, HIV-1 (IIIB) and HIV-2 (ROD), and some DNA viruses (adenovirus type 2 and herpes simplex virus type 1). The compound was shown to be active against rhinoviruses 2, 39, 86 and 89, Coxsackie B1 and measles virus
Between hope and disillusionment: ECMO seen through the lens of nurses working in a neonatal and paediatric intensive care unit
BACKGROUND: Using extracorporeal membrane oxygenation (ECMO) in paediatric and neonatal intensive care units (PICU/NICU) creates ethical challenges and carries a high risk for moral distress, burn out and team conflicts. AIM: The study aimed to gain a more comprehensive understanding of the underlying factors affecting moral distress when using ECMO for infants and children by examining the attitudes of ECMO nurses. METHODS: Four focus groups discussions were conducted with 21 critical care nurses working in a Swiss University Children's Hospital. Purposive sampling was adopted to identify research participants. The data were analysed using reflexive thematic analysis. RESULTS: Unlike "miracle machine" stories in online media reports, specialized nurses working in PICU/NICU expressed both their hopes and fears towards this technology. Their accounts also contained references to events and factors that triggered experiences of moral distress: the unspeakable nature of the death of a child or infant; the seemingly lack of honest and transparent communication with parents; the apparent loss of situational awareness among doctors; the perceived lack of recognition for the role of nurses and the variability in end-of-life decision-making; the length of time it takes doctors to take important treatment decisions; and the resource intensity of an ECMO treatment. CONCLUSION: The creation of a multidisciplinary moral community with transparent information among all involved health care professionals and the definition of clear treatment goals as well as the implementation of paediatric palliative care for all paediatric ECMO patients should become a priority if we want to alleviate situations of moral distress. RELEVANCE FOR CLINICAL PRACTICE: The creation of a multidisciplinary moral community, clear treatment goals and the implementation of palliative care for all paediatric ECMO patients are crucial to alleviate situations of moral distress for nurses, and thus to improve provider well-being and the quality of patient care in PICU/NICU
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