A sensitive method to determine 210Po and 210Pb in environmental samples by alpha spectrometry using CuS micro-precipitation.

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.

Lacan and Culturalism: A Chronicle of an "Untimely" Resistance to Psychoanalysis.

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.

[Therapeutic education, a necessity for people with haemophilia]. / L'éducation thérapeutique, une nécessité pour les personnes hémophiles.

Haemophilia is a chronic, restrictive and anxiety-inducing disease. In order to maintain a satisfactory quality of life, people can benefit from a therapeutic education programme to equip them with the skills they need to take care of their health.

ROUTINE METHOD FOR THE DETERMINATION OF TRACE AMOUNTS OF 226Ra IN URINE BY ALPHA SPECTROMETRY.

226Ra is considered one of the most radiotoxic naturally occurring radionuclides. A new routine method was developed to measure traces of 226Ra in urine. Radium was pre-concentrated from a 2 l urine sample using manganese oxide (MnO2) particles. The MnO2 precipitate was dissolved and the organic matter was broken down. Then, potential radiological interferents were removed using DGA and AGMP1 stacked resin columns. A barium sulphate (BaSO4) micro-precipitation was performed before measuring the sample by alpha spectrometry. A good recovery of 60 ± 10% and excellent alpha resolution were obtained. The minimum detectable activity (MDA) was 0.2 ± 0.1 mBql-1. The method was validated using spiked samples and can be completed in 5 hours.

The Lacanian Concept of Paranoia: An Historical Perspective.

This article seeks to reopen a major question raised by the Lacanian nosology of the psychoses, by looking closely at Lacan's formulations of what he never ceased referring to as "paranoia". While almost all classification systems of modern psychiatry, such as the ICD-10 and the DSM-5, have abandoned the specific category of paranoia, Lacan always viewed paranoia as a major category of "functional psychosis". He held that paranoia was a qualitatively different disorder than schizophrenia, and considered it to be the principal or exemplary form of psychosis. Furthermore, in the middle period of his work, Lacan thought of paranoia in much broader terms than those of the definition proposed by Kraepelin, which he revisited, point by point, developing his theory of Freud's concept of "Verwerfung" or foreclosure; the latter became the focal diagnostic criterion in his nosographic construction. Lacan's privileging of and evolving theoretical views on paranoia provide a structural approach to what he called the "resistant nucleus" of psychosis; his work serves as a counterpoint to the more descriptive neo-Kraepelinian approach of contemporary psychiatric nosology.

Determination of 99Tc in fresh water using TRU resin by ICP-MS.

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.

An improved method for the rapid determination of 90Sr in cow's milk.

An improved method was developed to rapidly determine strontium-90 (90Sr) 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 HNO3 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.

An emergency bioassay method for (210)Po in urine.

A rapid method was developed to efficiently measure (210)Po in urine samples in an emergency situation. Polonium-210 in small urine samples (10 mL) was spontaneously deposited on a stainless steel disc in 1 M HCl at room temperature for 4 h in a polyethylene bottle. The metallic disc was then counted for 4 h by alpha spectrometry. The developed method allowed the preparation of large sample batch in a short time. The method meets the requirements for an emergency bioassay procedure.

Freudian modalities of disbelief.

This article can be characterized as a 'rediscovery' of a notion of psychoanalysis that had disappeared or had been confused by later operations. The authors explore a Freudian notion that has been unjustly misunderstood, especially because of the multiple ways in which 'Unglaube' - disbelief - has been translated. We shall establish the archaeology of this term in Freud by extracting its three significant modes. Firstly, paranoiac disbelief designates an unconscious process of the rejection of belief in the subject's first encounter with a sexual reality that is always traumatic. Secondly, the obsessional neurotic's disbelief, which we shall call 'incredulity', is a secondary, less radical refusal of belief, one that is different from its paranoiac counterpart. Finally, we shall envision a third - dialectical - type of disbelief, which Freud called 'act of disbelief' and which will enable us to approach the fundamental epistemic and ethical stakes for psychoanalysis.

Determination of (210)Po in drinking water and urine samples using copper sulfide microprecipitation.

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.

Solvent-cast three-dimensional printing of multifunctional microsystems.

The solvent-cast direct-write fabrication of microstructures is shown using a thermoplastic polymer solution ink. The method employs the robotically controlled microextrusion of a filament combined with a rapid solvent evaporation. Upon drying, the increased rigidity of the extruded filament enables the creation of complex freeform 3D shapes.

Rapid preparation of polonium counting sources for alpha spectrometry using copper sulfide microprecipitation.

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 Cu(2+) 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 ((208)Po, (209)Po, (210)Po) are effectively removed during processing. The effects of several transition metals (Cu(2+), Ag(+), Fe(3+), Fe(2+), Pb(2+), and Ni(2+)) 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 (210)Po using (209)Po as a yield tracer.

Neptunium(III) application in extraction chromatography.

This paper describes a novel strategy for actinide separation by extraction chromatography with Np(III) valence adjustment. Neptunium(IV) was reduced to Np(III) using Cr(II) and then selectively separated from uranium (IV) on a TEVA resin. After elution, Np(III) was retained on a DGA resin in order to remove any detrimental chromium impurities. Neptunium(III) formation was demonstrated by the complete and selective elution of Np from TEVA resin (99 ± 7%) in less than 12 mL of 9M HCl from U(IV) (0.7 ± 0.7%). It was determined by UV-visible and kinetic studies that Cr(II) was the only species responsible for the elution of Np(IV) as Np(III) and that the Cr(II) solution could be prepared from 2 to 30 min before its use without the need of complex degassing systems to prevent the oxidation of Np(III) by oxygen. The methodology proposed here with TEVA/DGA resins provides removal of Cr(III) impurities produced at high decontamination factors (2.8 × 10(3) and 7.3 × 10(4) respectively).

Determination of neptunium in environmental samples by extraction chromatography after valence adjustment.

Neptunium(V) ions are unstable in acid media, which limits their extraction on chromatographic resins. We developed a novel analytical method to measure Np by either α-spectrometry or inductively coupled plasma mass spectrometry (ICP-MS) after extraction chromatography as Np(VI). We investigated the reactivity of various oxidizing reagents, and determined the retention capacity of Np(IV, V, and VI) on various extraction chromatographic supports. A simple method using two UTEVA resins was used to rapidly detect Np in soil and sediment samples.

A metamaterial for directive emission.

In this paper we present the first results on emission in metamaterial. We show how the specific properties of metallic composite material can modify the emission of an embedded source. We show that under proper conditions the energy radiated by a source embedded in a slab of metamaterial will be concentrated in a narrow cone in the surrounding media. An experimental demonstration of this effect is given in the microwave domain, and the constructed antenna has a directivity equivalent to the best reported results with photonic-crystal-based antennas but using a completely different physical principle [B. Temelkuaran, J. Appl. Phys. 87, 603 (2000)]].