A DGT Technique for Plutonium Bioavailability Measurements.

The toxicity of heavy metals in natural waters is strongly dependent on the local chemical environment. Assessing the bioavailability of radionuclides predicts the toxic effects to aquatic biota. The technique of diffusive gradients in thin films (DGT) is largely exploited for bioavailability measurements of trace metals in waters. However, it has not been applied for plutonium speciation measurements yet. This study investigates the use of DGT technique for plutonium bioavailability measurements in chemically different environments. We used a diffusion cell to determine the diffusion coefficients (D) of plutonium in polyacrylamide (PAM) gel and found D in the range of 2.06-2.29 × 10(-6) cm(2) s(-1). It ranged between 1.10 and 2.03 × 10(-6) cm(2) s(-1) in the presence of fulvic acid and in natural waters with low DOM. In the presence of 20 ppm of humic acid of an organic-rich soil, plutonium diffusion was hindered by a factor of 5, with a diffusion coefficient of 0.50 × 10(-6) cm(2) s(-1). We also tested commercially available DGT devices with Chelex resin for plutonium bioavailability measurements in laboratory conditions and the diffusion coefficients agreed with those from the diffusion cell experiments. These findings show that the DGT methodology can be used to investigate the bioaccumulation of the labile plutonium fraction in aquatic biota.

La technique au tribunal de l'éthique?

Ni technophile, ni technophobe, un éthicien s'interroge sur son rôle alors que la question de l'éthiquement correct se pose à lui de plus en plus souvent. Pourquoi cette urgence? A quel imaginaire renvoie-t-elle? Son hypothèse est la suivante: le monde technique serait désormais «la» nouvelle nature et il continue sa course quasi-automatiquement; il ferait ainsi de nous des «objets», par exemple de simples «épiphénomènes d'un programme génétique», à exploiter ou à surveiller. D'où notre besoin d'être rassurés.

Partir de soi, rencontrer l'autre--quelques réflexions sur la formation de psychiatre [The self and the other: a few comments on psychiatric education].

This manuscript has served for an oral presentation in honour of Professor Pierre Bovet who retired from his position as head physician at the Department of Psychiatry of the Lausanne University Hospital, Switzerland. Pierre Bovet has focused his clinical and scientific interest and his teaching activities on the schizophrenic spectrum disorders. The author tries to describe the essential elements of a clinical attitude which allows to really encounter the patient.

Natural killer cell mediated missing-self recognition can protect mice from primary chronic myeloid leukemia in vivo.

Background: Natural Killer (NK) cells are thought to protect from residual leukemic cells in patients receiving stem cell transplantation. However, multiple retrospective analyses of patient data have yielded conflicting conclusions regarding a putative role of NK cells and the essential NK cell recognition events mediating a protective effect against leukemia. Further, a NK cell mediated protective effect against primary leukemia in vivo has not been shown directly.Methodology/Principal Findings: Here we addressed whether NK cells have the potential to control chronic myeloid leukemia (CML) arising based on the transplantation of BCR-ABL1 oncogene expressing primary bone marrow precursor cells into lethally irradiated recipient mice. These analyses identified missing-self recognition as the only NK cell-mediated recognition strategy, which is able to significantly protect from the development of CML disease in vivo.Conclusion: Our data provide a proof of principle that NK cells can control primary leukemic cells in vivo. Since the presence of NK cells reduced the abundance of leukemia propagating cancer stem cells, the data raise the possibility that NK cell recognition has the potential to cure CML, which may be difficult using small molecule BCR-ABL1 inhibitors. Finally, our findings validate approaches to treat leukemia using antibody-based blockade of self-specific inhibitory MHC class I receptors.

Territorial autonomy and self-determination conflicts: opportunity and willingness cases from Bolivia, Niger, and Thailand

The paradox of autonomy is about whether self-rule accommodates or exacerbates armed conflict. This study attempts to unpack the puzzle examining the effectiveness of territorial autonomy as a state response to self-determination conflicts throughout the world. It challenges the conflict-inducing features of autonomy arguing that territorial autonomy can mitigate armed conflict by channeling group grievances into peaceful forms of protest. Thus, this study aims at arriving at a comprehensive theory that identifies which factors are responsible for violent escalation of conflicts grounded in self-determination demands. By using the concepts of opportunity structures and willingness dimension, this study shows that conflict escalation only takes place when minorities with greater bargaining power vis-à-vis the center, in contexts of high levels of economic inequality within dyad, are mobilized around autonomy and separatist demands.

Self-identity and religion/spirituality

Although medicine is practised in a secular setting, religious and spiritual issues have an impact on patient perspectives regarding their health and the management of any disorders that may afflict them. This is especially true in psychiatry, as feelings of spirituality and religiousness are very prevalent among the mentally ill. Clinicians are rarely aware of the importance of religion and understand little of its value as a mediating force for coping with mental illness. This book addresses various issues concerning mental illness in psychiatry: the relation of religious issues to mental health; the tension between a theoretical approach to problems and psychiatric approaches; the importance of addressing these varying approaches in patient care and how to do so; and differing ways to approach Christian, Muslim, and Buddhist patients. This is the first book to specifically cover the impact of religion and spirituality on mental illness.

How multiple repetitions influence the processing of self-, famous and unknown names and faces: an ERP study.

Because we live in an extremely complex social environment, people require the ability to memorize hundreds or thousands of social stimuli. The aim of this study was to investigate the effect of multiple repetitions on the processing of names and faces varying in terms of pre-experimental familiarity. We measured both behavioral and electrophysiological responses to self-, famous and unknown names and faces in three phases of the experiment (in every phase, each type of stimuli was repeated a pre-determined number of times). We found that the negative brain potential in posterior scalp sites observed approximately 170 ms after the stimulus onset (N170) was insensitive to pre-experimental familiarity but showed slight enhancement with each repetition. The negative wave in the inferior-temporal regions observed at approximately 250 ms (N250) was affected by both pre-experimental (famous>unknown) and intra-experimental familiarity (the more repetitions, the larger N250). In addition, N170 and N250 for names were larger in the left inferior-temporal region, whereas right-hemispheric or bilateral patterns of activity for faces were observed. The subsequent presentations of famous and unknown names and faces were also associated with higher amplitudes of the positive waveform in the central-parietal sites analyzed in the 320-900 ms time-window (P300). In contrast, P300 remained unchanged after the subsequent presentations of self-name and self-face. Moreover, the P300 for unknown faces grew more quickly than for unknown names. The latter suggests that the process of learning faces is more effective than learning names, possibly because faces carry more semantic information.

The Influence of Self-fertilization performance and Copulation Behaviour in Reproduction by Cross-fertilization in Groups of Biomphalaria tenagophila (Mollusca, Planorbidae)

The following hypotheses were tested for groups of simultaneous hermaphrodites Biomphalaria tenagophila: (a) snails that have low reproductive success during the process of self-fertilization do not increase their reproductive success after the end of grouping; (b) the copulation behaviour and the presence of one snail whose eggs have a low viability rate influence the partner's reproductive success by cross-fertilization. Groups were constituted by a homozygous pigmented snail and two albinos: one with a viability rate higher than 70% ("good reproducers") and the other less than 10% ("bad reproducers"). All pigmented snails had viability rates higher than 70%. The "good" and "bad" reproducer albino snails had similar copulation behaviour. However, after the end of grouping, the "bad reproducers" continued to have viability rates less than 10% over 30 days. In 100% of the cases that pigmented snails copulated (performing either a male role or simultaneously male and female roles) exclusively with "good" reproducer albinos, they presented high reproductive success (producing, on average of 8.4 pigmented embryos/egg-mass). However, in 100% of the cases that pigmented snails copulated with both partners, the "good" reproducer albino snails produced none or very few embryos (the highest average was 2.2 pigmented embryos/egg-mass). Therefore, the production of viable embryos by cross-fertilization was more influenced by self-fertilization performance than by copulation behaviour. The presence of a snail whose eggs have a low viability rate could decrease their partners reproductive success

Helminth Parasites of Conventionally Maintained Laboratory Mice: II- Inbred Strains with an Adaptation of the Anal Swab Technique

Worm burdens recovered from inbred mice strains, namely C57Bl/6, C57Bl/10, CBA, BALB/c, DBA/2 and C3H/He, conventionally maintained in two institutional animal houses in the State of Rio de Janeiro, RJ, Brazil, were analyzed and compared, regarding their prevalences and mean intensities.Three parasite species were observed: the nematodes Aspiculuris tetraptera, Syphacia obvelata and the cestode Vampirolepis nana. A modification of the anal swab technique is also proposed for the first time as an auxiliary tool for the detection of oxyurid eggs in mice