Although neither Sigmund Freud nor Jacques Lacan ever neglected the place of culture and the social field for the subject, they always opposed “culturalist” ideas, even when such ideas no longer used ...this label. It is important to examine what both of these figures said about culturalism, but it is just as pertinent to return to other criticisms of this movement, which developed in the United States during the last century, because at present this movement has returned covertly within French psychoanalysis. First, “culturalism” is neither a specifically American problem nor one that belongs to the past. Second, some decisive criticisms of this movement remain both germane and original: they are able to throw light on a theoretical current that, at least in France, now characterizes a dominant orientation of psychoanalytic work. Third, although Lacan himself foresaw it, the misuse of some of his notions has unexpectedly served as a Trojan horse that has enabled culturalism to return.
Technetium-99 (99Tc) determination at trace level by inductively coupled plasma mass spectrometry (ICP-MS) is challenging because there is no readily available appropriate Tc isotopic tracer. A new ...method using Re as a recovery tracer to determine 99Tc in fresh water samples, which does not require any evaporation step, was developed. Tc(VII) and Re(VII) were pre-concentrated on a small anion exchange resin (AER) cartridge from one litre of water sample. They were then efficiently eluted from the AER using a potassium permanganate (KMnO4) solution. After the reduction of KMnO4 in 2 M sulfuric acid solution, the sample was passed through a small TRU resin cartridge. Tc(VII) and Re(VII) retained on the TRU resin were eluted using near boiling water, which can be directly used for the ICP-MS measurement. The results for method optimisation, validation and application were reported.
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•Tc(VII) can be extracted and purified from potential interferents with a TRU resin.•Re(VII) can be used as a recovery tracer.•No vaporisation step is needed for this method.•Potassium permanganate can be used to elute Tc(VII) and Re(VII) from an anion exchange resin.•A low detection limit of 4.01 × 10−13 Bq·L−1 was obtained.
An improved method was developed to rapidly determine strontium-90 (
Sr) in cow's milk samples in the event of a nuclear emergency. To perform this method, no heating or ashing steps were needed and ...all of the material used was disposable. Stable Sr tracer was added to each 40 mL milk sample. Hydrochloric acid (HCl) and trichloroacetic acid (TCA) were added to the sample to flocculate the suspended fat and proteins in the milk. The sample was centrifuged and the strontium in the supernatant was precipitated with carbonate. The resulting precipitate was dissolved in 8 M HNO
and the solution was passed through a Sr resin to remove potential interferents. Strontium was eluted from the resin using a small volume of water. Strontium-90 was measured by liquid-scintillation counting (LSC) and the tracer by inductively coupled plasma mass spectrometry (ICP-MS). The figures of merit of the method were determined and the method was validated using spiked samples.
A new sensitive method to determine polonium-210 (210Po) and lead-210 (210Pb) in a diversity of environmental samples was developed. For fresh and marine waters, Po was pre-concentrated using a ...titanium (III) hydroxide (Ti(OH)3) co-precipitation. Solid environmental samples were digested with nitric acid (HNO3) and hydrogen peroxide (H2O2). The alpha thin layer source was prepared using CuS micro-precipitation and 210Po was measured by alpha spectrometry. Lead-210 was left to decay for up to a year and indirectly measured via its progeny, 210Po. The chemical recoveries for 210Po and 210Pb were high, 90% and 97%, respectively, for a large variety of samples and a very low minimum detectable activity (MDA) was obtained. The method was validated using standardized solutions and certified reference materials.
Thin-layer polonium (Po) sources for alpha spectrometry counting can be rapidly prepared using copper sulfide (CuS) microprecipitation. Polonium was coprecipitated with CuS, filtered onto Eichrom ...Resolve filters, and counted. This simple procedure is faster, cheaper, and more convenient than traditional spontaneous plating on metallic discs, and similar yields were obtained (80–90%). The experimental conditions for the microprecipitation technique were optimized (0.05 mg of Cu2+ in 10 mL of 1 M HCl); these compare advantageously with conventional preparation and purification procedures for polonium samples (0.1 to 1 M HCl). The results showed that the most likely potential radionuclide interferences (Ra, Th, U, Np, Pu, and Am) for long-lived polonium isotopes (208Po, 209Po, 210Po) are effectively removed during processing. The effects of several transition metals (Cu2+, Ag+, Fe3+, Fe2+, Pb2+, and Ni2+) on the yield and the resolution of the alpha peaks obtained were also assessed. Little interference was found, demonstrating the versatility of the present microprecipitation technique for environmental and biological matrices. The procedure has been successfully applied to different amounts of 210Po using 209Po as a yield tracer.
A new method to determine
226
Ra by alpha spectrometry from various environmental samples was developed. After sample dissolution, Ra(II) was co-precipitated with PbSO
4
, and the precipitate was ...quickly filtered 1 min later. The rapid filtration of PbSO
4
prevented CaSO
4
and SrSO
4
from precipitating. The Pb(Ra)SO
4
precipitate was re-dissolved using an EDTA solution and the pH was adjusted to 5 with sulfuric acid. Then, a BaSO
4
micro-precipitation was performed to prepare a Ra thin-layer source for measurement of
226
Ra by alpha spectrometry. Excellent decontamination factors were obtained. The method was validated using spiked samples and certified reference materials.
Visual localization, i.e., camera pose estimation in a known scene, is a core component of technologies such as autonomous driving and augmented reality. State-of-the-art localization approaches ...often rely on image retrieval techniques for one of two purposes: (1) provide an approximate pose estimate or (2) determine which parts of the scene are potentially visible in a given query image. It is common practice to use state-of-the-art image retrieval algorithms for both of them. These algorithms are often trained for the goal of retrieving the same landmark under a large range of viewpoint changes which often differs from the requirements of visual localization. In order to investigate the consequences for visual localization, this paper focuses on understanding the role of image retrieval for multiple visual localization paradigms. First, we introduce a novel benchmark setup and compare state-of-the-art retrieval representations on multiple datasets using localization performance as metric. Second, we investigate several definitions of "ground truth" for image retrieval. Using these definitions as upper bounds for the visual localization paradigms, we show that there is still significant room for improvement. Third, using these tools and in-depth analysis, we show that retrieval performance on classical landmark retrieval or place recognition tasks correlates only for some but not all paradigms to localization performance. Finally, we analyze the effects of blur and dynamic scenes in the images. We conclude that there is a need for retrieval approaches specifically designed for localization paradigms. Our benchmark and evaluation protocols are available at
Polonium-210 ((210)Po) can be rapidly determined in drinking water and urine samples by alpha spectrometry using copper sulfide (CuS) microprecipitation. For drinking water, Po in 10 mL samples was ...directly coprecipitated onto the filter for alpha counting without any purification. For urine, 10 mL of sample was heated, oxidized with KBrO3 for a short time (∼5 min), and subsequently centrifuged to remove the suspended organic matter. The CuS microprecipitation was then applied to the supernatant. Large batches of samples can be prepared using this technique with high recoveries (∼85%). The figures of merit of the methods were determined, and the developed methods fulfill the requirements for emergency and routine radioassays. The efficiency and reliability of the procedures were confirmed using spiked samples.
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