The reflexive potential of silence:Emotions, the ‘everyday’ and ethical international relations

This article argues on behalf of an autoethnographic methodology as one, but not the only, method suited to the excavation of the emotions of everyday international relations. I suggest, drawing on my own lived experiences of writing the Life in the United Kingdom Test specifically, and being ordered deported from the United Kingdom more broadly, that a reflexive practice informed by silence allows scholars to attend to the otherwise discounted and excluded forms of emotional knowledge. As my story unfolds, and the transformative potential of trauma is rehearsed, the possibility of excavating otherwise silenced emotions, guided by an affective empathy, comes to the fore. I suggest, building on my own lived experience, that as the researcher cum agent embraces this position, discounted and discarded stories are revisited. In so doing I present a piece of evocative autoethnography in and of itself while demonstrating the role that emotions can play in the construction of everyday practices of International Relations

NCAM180 Regulates Ric8A Membrane Localization and Potentiates β-Adrenergic Response

Cooperation between receptors allows integrated intracellular signaling leading to appropriate physiological responses. The Neural Cell Adhesion Molecule (NCAM) has three main isoforms of 120, 140 and 180 kDa, with adhesive and signaling properties, but their respective functions remains to be fully identified. Here we show that the human NCAM180 intracellular domain is a novel interactor of the human guanosine exchange factor (GEF) Ric8A using the yeast two hybrid system and immunoprecipitation. Furthermore, NCAM, Ric8A and Gαs form a tripartite complex. Colocalization experiments by confocal microscopy revealed that human NCAM180 specifically induces the recruitment of Ric8A to the membrane. In addition, using an in vitro recombinant system, and in vivo by comparing NCAM knock-out mouse brain to NCAM heterozygous and wild type brains, we show that NCAM expression dose dependently regulates Ric8A redistribution in detergent resistent membrane microdomains (DRM). Previous studies have demonstrated essential roles for Ric8 in Gα protein activity at G protein coupled receptors (GPCR), during neurotransmitter release and for asymmetric cell division. We observed that inhibition of Ric8A by siRNA or its overexpression, decreases or increases respectively, cAMP production following β-adrenergic receptor stimulation. Furthermore, in human HEK293T recombinant cells, NCAM180 potentiates the Gαs coupled β-adrenergic receptor response, in a Ric8A dependent manner, whereas NCAM120 or NCAM140 do not. Finally, in mouse hippocampal neurons expressing endogenously NCAM, NCAM is required for the agonist isoproterenol to induce cAMP production, and this requirement depends on Ric8A. These data illustrate a functional crosstalk between a GPCR and an IgCAM in the nervous system

Mesoporous Silica Nanoparticles Loaded with Surfactant: Low Temperature Magic Angle Spinning 13C and 29Si NMR Enhanced by Dynamic Nuclear Polarization

We show that dynamic nuclear polarization (DNP) can be used to enhance NMR signals of13C and 29Si nuclei located in mesoporous organic/inorganic hybrid materials, at several hundreds of nanometers from stable radicals (TOTAPOL) trapped in the surrounding frozen disordered water. The approach is demonstrated using mesoporous silica nanoparticles (MSN), functionalized with 3-(N-phenylureido)propyl (PUP) groups, filled with the surfactant cetyltrimethylammonium bromide (CTAB). The DNP-enhanced proton magnetization is transported into the mesopores via 1H–1H spin diffusion and transferred to rare spins by cross-polarization, yielding signal enhancements εon/off of around 8. When the CTAB molecules are extracted, so that the radicals can enter the mesopores, the enhancements increase to εon/off ≈ 30 for both nuclei. A quantitative analysis of the signal enhancements in MSN with and without surfactant is based on a one-dimensional proton spin diffusion model. The effect of solvent deuteration is also investigated

Structure and Ionic Conductivity in the Mixed-Network Former Chalcogenide Glass System [Na2S]2/3[(B2S3)x(P2S5)1–x]1/3

Glasses in the system [Na2S]2/3[(B2S3)x(P2S5)1–x]1/3 (0.0 ≤ x ≤ 1.0) were prepared by the melt quenching technique, and their properties were characterized by thermal analysis and impedance spectroscopy. Their atomic-level structures were comprehensively characterized by Raman spectroscopy and 11B, 31P, and 23Na high resolution solid state magic-angle spinning (MAS) NMR techniques. 31P MAS NMR peak assignments were made by the presence or absence of homonuclear indirect 31P–31P spin–spin interactions as detected using homonuclear J-resolved and refocused INADEQUATE techniques. The extent of B–S–P connectivity in the glassy network was quantified by 31P{11B} and 11B{31P} rotational echo double resonance spectroscopy. The results clearly illustrate that the network modifier alkali sulfide, Na2S, is not proportionally shared between the two network former components, B and P. Rather, the thiophosphate (P) component tends to attract a larger concentration of network modifier species than predicted by the bulk composition, and this results in the conversion of P2S74–, pyrothiophosphate, Na/P = 2:1, units into PS43–, orthothiophosphate, Na/P = 3:1, groups. Charge balance is maintained by increasing the net degree of polymerization of the thioborate (B) units through the formation of covalent bridging sulfur (BS) units, B–S–B. Detailed inspection of the 11B MAS NMR spectra reveals that multiple thioborate units are formed, ranging from neutral BS3/2 groups all the way to the fully depolymerized orthothioborate (BS33–) species. On the basis of these results, a comprehensive and quantitative structural model is developed for these glasses, on the basis of which the compositional trends in the glass transition temperatures (Tg) and ionic conductivities can be rationalized. Up to x = 0.4, the dominant process can be described in a simplified way by the net reaction equation P1 + B1 P0 + B4, where the superscripts denote the number of BS atoms for the respective network former species. Above x = 0.4, all of the thiophosphate units are of the P0 type and both pyro- (B1) and orthothioborate (B0) species make increasing contributions to the network structure with increasing x. In sharp contrast to the situation in sodium borophosphate glasses, four-coordinated thioborate species are generally less abundant and heteroatomic B–S–P linkages appear to not exist. On the basis of this structural information, compositional trends in the ionic conductivities are discussed in relation to the nature of the charge-compensating anionic species and the spatial distribution of the charge carriers

Structural and spatially-resolved studies on the hardening of a commercial resin-modified glass-ionomer cement

A commercial photopolymerizable resinmodified glass-ionomer (Fuji II LC) was studied using a variety of nuclear magnetic resonance (NMR) techniques. H and F stray-field imaging (STRAFI) enabled to follow the acid–base reaction kinetics in self-cured (SC) samples. Gelation and maturation processes with 25 min and 40 h average time constants, respectively, were distinguished. In self- & photo-cured (SPC) samples, two processes were also observed, which occurred with 2 s and 47 s average time constants. H, Al and Si magic angle spinning (MAS) NMR, C cross-polarization (CP)/MAS NMR and 27Al multiple quanta (MQ)MAS NMR spectroscopy were used to obtain structural information on the glass and cements that were either SC or SPC. The presence of methacrylate groups was identified in the solid component. Unreacted hydroxyl ethylmethacrylate (HEMA) was detected in self-cured cement. Al data showed that approximately 28% and 20% of Al is leached out from glass particles in SC and SPC samples, respectively. The upfield shift detected in 25Si MAS NMR spectra of the cements is consistent with a decrease in the number of Al species in the second coordination sphere of the silicon structures. Scanning electron microscopy (SEM) showed existence of 3D shrinkage of the cement matrix in photo-cured cements.(undefined

High resolution incoherent quasielastic neutron scattering study of molecular reorientations of trimethylacetic acid (CH3) 3CCOOD in its low-temperature phase

Using the incoherent quasielastic neutron scattering technique, we have studied the molecular reorientations of partially deuterated trimethylacetic acid (CH3)3CCOOD in its low temperature phase. The measurements were carried out with a sample temperature in the range from 80 K to 254 K, using an incoming neutron wavelength λ = 6.28 Å. The observed quasielastic spectra are consistent with a model allowing a combination of 120°-reorientations of the methyl and t-butyl groups.La diffusion quasi élastique incohérente des neutrons a permis d'étudier les réorientations moléculaires de l'acide triméthylacétique partiellement deutéré (CH3)3 CCOOD dans sa phase basse température. Les mesures ont été effectuées dans un domaine de température allant de 80 K à 254 K, en utilisant une longueur d'onde des neutrons incidents λ = 6,28 Å. Les spectres quasi élastiques observés peuvent être convenablement décrits par un modèle combinant simultanément des réorientations de 120° des groupements méthyles et t-butyles

Quantitative study of the short range order in B2O3 and B2S3 by MAS and two-dimensional triple-quantum MAS B-11 NMR

Two-dimensional multiple-quantum magic angle spinning (MQMAS) NMR and MAS NMR of B-11 at various magnetic fields, were applied to elucidate the structure of vitreous (glassy) boron trioxide (v-B2O3), vitreous boron trisulfide (v-B2S3) and crystalline boron trisulfide (c-B2S3). These techniques, when combined with computer simulations of the resulting spectra, provide the isotropic chemical shifts and the quadrupole parameters, as well as a quantitative measure of the intensities of various boron resonances. The MAS NMR of v-B2O3 produced overlapping anisotropic lineshapes corresponding to the -1/2 1/2 transition in two distinct types of BO3 units with 3(+/-0.08):1 intensity ratio. A combination of MAS and the multiple-quantum method resulted in a better resolved, isotropic B-11 spectrum of v-B2O3. A remarkable enhancement of resolution of the MQMAS NMR proved instrumental in finding and identifying various impurities present in V-B2S3 and c-B2S3. In addition to the resonances from boron in two types of BS, groups, four other structural units, BOS,, BO2S, BO3 and BS4, were elucidated from the spectra of vitreous and crystalline samples. The effects of various experimental parameters, such as the magnitude of the B-0 and B-1 fields, on the resolution of the MAS and MQMAS techniques are also shown.close585

Evolution des peuplements des fonds cotiers au large du bassin d'Arcachon

This study deals with the evolution of a fine sand benthic community located in shallow water off Arcachon Bay in an area which receives effluent from domestic and industrial sources. Comparison between 1974 and 1979 samplings shows trophic structure fluctuations. In 1979, the community is characterized by a dominance of deposit feeders with a decrease of suspension-feeders and carnivores. An effects of the sewage is not proved. The sedimentation of fine elements is proposed to explain the changes of trophic structure. It is suggested that these fluctuations are governed either by water movements or by long period sedimentary cycles

Multiple-quantum 27Al MAS NMR spectroscopy of microporous AlPO-40 and SAPO-40

Two-dimensional triple- and quintuple-quantum 27AI magic-angle spinning (MO MAS) n.m.r. spectra of microporous AIPO-40 and SAPOBO have been recorded at 9.4 and 14.1 T. The resolution of the 5Q spectra of AIPO-40 is amazing, at least 11 resonances being resolved. The 3lQ spectra further reveal the presence of 2 other much fainter peaks. Because the AIPO-40 aluminium sites have different quadrupole coupling constants the 9.4 T spectra are slightly better resolved than the 14.1 T spectra, suggesting that in MO n.m.r. it may sometimes be advantageous to work at lower magnetic fields. The 3Q spectra of SAPO-40 are poorly resolved displaying a main broad peak and two faint resonances. This is because the introduction of even a small amount of Si into the framework of AIPO-40 generates a distribution of Al sites and a dispersion of chemical shifts. MQ 27AI MAS n.m.r. together with 31P MAS n.m.r. evidence discard an orthorhombic, Pccn, and monoclinic, P172/n, structure for as-prepared or calcined dehydrated AIPO-40, suggesting a space group with even lower symmetry that proposed to date