553 research outputs found
Ovarian vein thrombosis in a polytrauma patient
A young mother presented to a Major Trauma Centre (MTC) following a road traffic collision. Her admission computed tomography (CT) traumagram demonstrated liver and renal lacerations, spinal and pelvic fractures with no abnormalities of the ovarian veins. Her inpatient course was uncomplicated other than a sustained, isolated raised c-reactive protein (CRP). CT abdomen one week after injury demonstrated stable solid organ injuries and the additional, unexpected finding of a right ovarian vein thrombosis (OVT). A pragmatic approach was taken towards the management of the OVT given the haemorrhagic risk from her traumatic injuries. A multi-disciplinary, consultant-led plan was made to slowly increase enoxaparin to a therapeutic dose under close surveillance and to then switch to warfarin following an outpatient consultation with a consultant haematologist. A magnetic resonance venogram was performed after 3 months of anticoagulation and this demonstrated complete resolution of the OVT and normal appearances of the ovary
Management of Constipation
Constipation is the most ignored complaint by doctors and unfortunately, it requires urgent management due to the decreased quality of life. Most cases are functional constipation but there is also a great number of constipation due to organic abnormalities. In an attempt to manage the patient properly, we should put our emphasis on excellent knowledge of pathophysiology of constipation.By using the colonic transit time test, we could determine the type of constipation, which would have an effect on therapy. In most cases, constipation has a good response to high fiber diet and additional laxative medication and surgical therapy is seldom required unless complications have occurred. There is also a suggestion for preventing constipation may be caused by opioid USAge
Structural stability of Fe5Si3 and Ni2Si studied by high-pressure x-ray diffraction and ab initio total-energy calculations
We performed high-pressure angle dispersive x-ray diffraction measurements on
Fe5Si3 and Ni2Si up to 75 GPa. Both materials were synthesized in bulk
quantities via a solid-state reaction. In the pressure range covered by the
experiments, no evidence of the occurrence of phase transitions was observed.
On top of that, Fe5Si3 was found to compress isotropically, whereas an
anisotropic compression was observed in Ni2Si. The linear incompressibility of
Ni2Si along the c-axis is similar in magnitude to the linear incompressibility
of diamond. This fact is related to the higher valence-electron charge density
of Ni2Si along the c-axis. The observed anisotropic compression of Ni2Si is
also related to the layered structure of Ni2Si where hexagonal layers of Ni2+
cations alternate with graphite-like layers formed by (NiSi)2- entities. The
experimental results are supported by ab initio total-energy calculations
carried out using density functional theory and the pseudopotential method. For
Fe5Si3, the calculations also predicted a phase transition at 283 GPa from the
hexagonal P63/mcm phase to the cubic structure adopted by Fe and Si in the
garnet Fe5Si3O12. The room-temperature equations of state for Fe5Si3 and Ni2Si
are also reported and a possible correlation between the bulk modulus of iron
silicides and the coordination number of their minority element is discussed.
Finally, we report novel descriptions of these structures, in particular of the
predicted high-pressure phase of Fe5Si3 (the cation subarray in the garnet
Fe5Si3O12), which can be derived from spinel Fe2SiO4 (Fe6Si3O12).Comment: 44 pages, 13 figures, 3 Table
Redetermination of eveite, Mn2AsO4(OH), based on single-crystal X-ray diffraction data
The crystal structure of eveite, ideally Mn2(AsO4)(OH) [dimanganese(II) arsenate(V) hydroxide], was refined from a single crystal selected from a co-type sample from Långban, Filipstad, Varmland, Sweden. Eveite, dimorphic with sarkinite, is structurally analogous with the important rock-forming mineral andalusite, Al2OSiO4, and belongs to the libethenite group. Its structure consists of chains of edge-sharing distorted [MnO4(OH)2] octahedra (..2 symmetry) extending parallel to [001]. These chains are cross-linked by isolated AsO4 tetrahedra (..m symmetry) through corner-sharing, forming channels in which dimers of edge-sharing [MnO4(OH)] trigonal bipyramids (..m symmetry) are located. In contrast to the previous refinement from Weissenberg photographic data [Moore & Smyth (1968 ▶). Am. Mineral.
53, 1841–1845], all non-H atoms were refined with anisotropic displacement parameters and the H atom was located. The distance of the donor and acceptor O atoms involved in hydrogen bonding is in agreement with Raman spectroscopic data. Examination of the Raman spectra for arsenate minerals in the libethenite group reveals that the position of the peak originating from the O—H stretching vibration shifts to lower wavenumbers from eveite, to adamite, zincolivenite, and olivenite
The cost of cooking a meal. The case of Nyeri County, Kenya
Energy for cooking is considered essential in achieving modern energy access. Despite this, almost three billion people worldwide still use solid fuels to meet their cooking needs. To better support practitioners and policy-makers, this paper presents a new model for comparing cooking solutions and its key output metric: the 'levelized cost of cooking a meal' (LCCM). The model is applied to compare several cooking solutions in the case study area of Nyeri County in Kenya. The cooking access targets are connected to the International Workshop Agreement and Global Tracking Framework's tiers of cooking energy access. Results show how an increased energy access with improved firewood and charcoal cookstoves could reduce both household's LCCMs and the total costs compared to traditional firewood cooking over the modelling period. On the other hand, switching to cleaner cooking solutions, such as LPG- and electricity, would result in higher costs for the end-user highlighting that this transition is not straightforward. The paper also contextualizes the results into the wider socio-economic context. It finds that a tradeoff is present between minimizing costs for households and meeting household priorities, thus maximizing the potential benefits of clean cooking without dismissing the use of biomass altogether
Evidence-based Languages for Conceptual Data Modelling Profiles
To improve database system quality as well as runtime use of conceptual models, many logic-based reconstructions of conceptual data modelling languages have been proposed in a myriad of logics. They each cover their features to a greater or lesser extent and are typically motivated from a logic viewpoint. This raises questions such as what would be an evidence-based common core and what is the optimal language profile for a conceptual modelling language family. Based on a common metamodel of UML Class Diagrams (v2.4.1), ER/EER, and ORM/2's static elements, a set of 101 conceptual models, and availing of computational complexity insights from Description Logics, we specify these profiles. There is no known DL language that matches exactly the features of those profiles and the common core is small (in the tractable ). Although hardly any inconsistencies can be derived with the profiles, it is promising for scalable runtime use of conceptual data models
A Reference High-Pressure CO2\u3c/sub\u3e Adsorption Isotherm for Ammonium ZSM-5 Zeolite: Results of an Interlaboratory Study
© 2018, The Author(s). This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess carbon dioxide adsorption isotherms on NIST Reference Material RM 8852 (ammonium ZSM-5 zeolite), at 293.15 K (20 °C) from 1 kPa up to 4.5 MPa. Eleven laboratories participated in this exercise and, for the first time, high-pressure adsorption reference data are reported using a reference material. An empirical reference equation nex=d(1+exp[(-ln(P)+a)/b])c, [nex-surface excess uptake (mmol/g), P-equilibrium pressure (MPa), a = −6.22, b = 1.97, c = 4.73, and d = 3.87] along with the 95% uncertainty interval (Uk = 2 = 0.075 mmol/g) were determined for the reference isotherm using a Bayesian, Markov Chain Monte Carlo method. Together, this zeolitic reference material and the associated adsorption data provide a means for laboratories to test and validate high-pressure adsorption equipment and measurements. Recommendations are provided for measuring reliable high-pressure adsorption isotherms using this material, including activation procedures, data processing methods to determine surface excess uptake, and the appropriate equation of state to be used
Long-range corrected DFT calculations of charge-transfer integrals in model metal-free phthalocyanine complexes
An assessment of several widely used exchange--correlation potentials in computing charge-transfer integrals is performed. In particular, we employ the recently proposed Coulomb-attenuated model which was proven by other authors to improve upon conventional functionals in the case of charge-transfer excitations. For further validation, two distinct approaches to compute the property in question are compared for a phthalocyanine dimer
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