90 research outputs found
Determining geophysical responses from burials in graveyards and cemeteries
Graveyards and cemeteries around the world are increasingly designated as full. Therefore, there is a requirement to identify vacant spaces for new burials or to identify existing ones to exhume and then reinter if necessary. Geophysical methods offer a potentially noninvasive target detection solution; however, there has been limited research to identify optimal geophysical detection methods against burial age. We have collected multifrequency (225–900 MHz) ground-penetrating radar (GPR), electrical resistivity, and magnetic susceptibility surface data over known graves with different burial ages and soil types in three UK church graveyards. Results indicate that progressively older burials are more difficult to detect, but this decrease is not linear and is site specific. Medium- to high-frequency GPR and magnetic susceptibility was optimal in clay-rich soils, medium- to high-frequency GPR and electrical resistivity in sandy soils, and electrical resistivity and low-frequency GPR in coarse sand and pebbly soils, respectively. A multigeophysical technique approach should be used by survey practitioners where grave locations are not known to maximize target detection success. Grave soil and grave cuts are important grave position indicators. Grave headstones were not always located where burials were located. We have determined the value of these techniques in grave detection and could potentially date burials from their geophysical responses
Novel spectrophotometric method for the determination of azithromycin in pharmaceutical formulations based on its charge transfer reaction with quinalizarin
This paper proposes a new method for simple and fast spectrophotometric determination of azithromycin in pharmaceutical formulations. The method is based on the charge transfer reaction between the azithromycin and quinalizarin in methanol medium. In order to achieve maximum sensitivity the effect of some chemical variables such as the type of solvent, reagent concentration and reaction time were evaluated. The reaction was characterized in terms of stability of the product formed and its stoichiometry, and the apparent molar absorptivity and association constant were derived. Best conditions for the analytical determination of azithromycin were observed in methanol medium with a quinalizarin concentration of 50 mg L-1. At these conditions, the radical anion (absorbing specie) was formed in the medium immediately after mixing of the reagents and showed maximum absorption at 564 nm. The method presented a limit of detection of 0.35 mg L-1 and a limit of quantification of 1.2 mg L-1. It was successfully applied in the determination of azithromycin in three commercial pharmaceutical formulations of azithromycin and no matrix interferences were observed
Mid-circuit qubit measurement and rearrangement in a Yb atomic array
Measurement-based quantum error correction relies on the ability to determine
the state of a subset of qubits (ancillae) within a processor without revealing
or disturbing the state of the remaining qubits. Among neutral-atom based
platforms, a scalable, high-fidelity approach to mid-circuit measurement that
retains the ancilla qubits in a state suitable for future operations has not
yet been demonstrated. In this work, we perform imaging using a
narrow-linewidth transition in an array of tweezer-confined Yb atoms to
demonstrate nondestructive state-selective and site-selective detection. By
applying site-specific light shifts, selected atoms within the array can be
hidden from imaging light, which allows a subset of qubits to be measured while
causing only percent-level errors on the remaining qubits. As a
proof-of-principle demonstration of conditional operations based on the results
of the mid-circuit measurements, and of our ability to reuse ancilla qubits, we
perform conditional refilling of ancilla sites to correct for occasional atom
loss, while maintaining the coherence of data qubits. Looking towards true
continuous operation, we demonstrate loading of a magneto-optical trap with a
minimal degree of qubit decoherence.Comment: 9 pages, 6 figure
First international consensus on the methodology of lymphangiogenesis quantification in solid human tumours
The lymphatic system is the primary pathway of metastasis for most human cancers. Recent research efforts in studying lymphangiogenesis have suggested the existence of a relationship between lymphatic vessel density and patient survival. However, current methodology of lymphangiogenesis quantification is still characterised by high intra- and interobserver variability. For the amount of lymphatic vessels in a tumour to be a clinically useful parameter, a reliable quantification technique needs to be developed. With this consensus report, we therefore would like to initiate discussion on the standardisation of the immunohistochemical method for lymphangiogenesis assessment
Microwave-Assisted Extraction of Chloride Followed by Ion Chromatography as an Alternative to the ASTM D6470 Method for the Determination of Crude Oil Salinity
The presence of chloride in crude oil can result in a number of drawbacks, with technical and economic impacts on
the production of petroleum derivatives. For this reason, it must be carefully monitored in this kind of sample. In this work, we
developed a simple and efficient method for the determination of chloride in crude oil by ion chromatography with conductivity
detection after microwave-assisted extraction. The method was optimized using a multivariate strategy based on the use of a twolevel
full factorial design for the screening of significant factors and a Doehlert matrix for their optimization. Four factors were
selected in this study: mass of the sample, extraction temperature, extraction time, and the volume of toluene employed to disperse
the sample. Under optimized conditions, 1.10 g of the sample was dispersed in 3.0 mL of toluene and 10 mL of deionized water was
added. The mixture was irradiated for 25 min at 146 °C (extraction temperature). After cooling, the mixture was centrifuged for 15
min at 5000 rpm for separation of the phases, and the aqueous extract was filtered and analyzed by ion chromatography. The limits
of detection and quantification of the method were 0.13 and 0.39 μg g−1, respectively. The method was applied in the determination
of chloride in four samples of crude oil, and the obtained results were statistically similar to those obtained by the reference method
(ASTM D6470).UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Químic
Seizing the Proceeds of Crime: A critical analysis of how the law and practice work in key Jurisdictions
Theme: Economic Crime - Surviving the Fall, the Myths and Realitie
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