89Y NMR Probe of Zn Induced Local Magnetism in YBa2(Cu(1-y)Zn(y))3O(6+x)

We present detailed data and analysis of the effects of Zn substitution on the planar Cu site in YBa$_2$Cu$_3$O$_{6+x}$ (YBCO$_{6+x}$) as evidenced from our $^{89}$Y NMR measurements on oriented powders. For $x<<1$ we find additional NMR lines which are associated with the Zn substitution. From our data on the intensities and temperature dependence of the shift, width, and spin-lattice relaxation rate of these resonances, we conclude that the spinless Zn 3$d$$^{10}$ state induces local moments on the near-neighbour ($$) Cu atoms. Additionally, we conjecture that the local moments actually extend to the farther Cu atoms with the magnetization alternating in sign at subsequent $nn$ sites. We show that this analysis is compatible with ESR data taken on dilute Gd doped (on the Y site) and on neutron scattering data reported recently on Zn substituted YBCO$_{6 + x}$. For optimally doped compounds $^{89}$Y $nn$ resonances are not detected, but a large $T$% -dependent contribution to the $^{89}$Y NMR linewidth is evidenced and is also attributed to the occurence of a weak induced local moment near the Zn. These results are compatible with macroscopic magnetic measurements performed on YBCO$_{6 + x}$ samples prepared specifically in order to minimize the content of impurity phases. We find significant differences between the present results on the underdoped YBCO$_{6 + x}$ samples and $$Al NMR data taken on Al$^{3+}$ substituted on the Cu site in optimally doped La$_2$CuO$_4$. Further experimental work is needed to clarify the detailed evolution of the impurity induced magnetism with hole content in the cuprates.Comment: To be published in EPJB 15 pages of text and figures in eps forma

Hanoi Vietnam’s Peri-urban Space and Its Impact on People’s Livelihoods

ABSTRACT Hanoi Vietnam’s Peri-urban Space and Its Impact on People’s Livelihoods Collin V. Sumera Peri-urban is both a space and a process, yet there is no cookie cutter definition that may be applied to developing cities encountering this phenomenon. Each space is constructed differently, and each process has different actors. This paper examines the role that the Communist Party of Vietnam plays in the creation of peri-urban space in Hanoi, and how this space affects residential and former agricultural Land Use Right holder’s livelihood opportunities. The notion of the peri-urban space has not fully been developed for Hanoi, thus I conclude that due to the establishment of policies made within the market economy, state-owned enterprises and corrupt practices on different governmental levels; these gaps and malpractices have led to illegal acts of land grabbing creating peri-urban spaces that disrupt Land Use Right holder’s livelihood practices. Defining peri-urban in the context of Hanoi better informs development and humanitarian agencies seeking to work with marginalized groups and to assist in the creation of livelihood opportunities

59Co NMR study of the Co states in superconducting and anhydrous cobaltates

$^{59}$Co NMR spectra in oriented powders of Na$_{0.35}$CoO$_{2}$ and in its hydrated superconducting phase (HSC) Na$_{0.35}$CoO$_{2}$,1.3H$_{2}$O reveal a single electronic Co state with identical $T$ independent NMR shift tensor. These phases differ markedly from Na$_{0.7}$CoO$_{2}$, in which we resolve 3 types of Co sites. The large T variation of their spin susceptibilities $\chi ^{s}$ and the anisotropy of the orbital susceptibility $\chi ^{orb}$ allow us to conclude that charge disproportionation occurs, in a non magnetic Co$^{3+}$ and two magnetic sites with about 0.3 and 0.7 holes in the $t_{2g}$ multiplet. The data are consistent with those for the single Co site in the anhydrous and HSC phase assuming the expected Co$^{3.65+}$ charge.Comment: 5 pages, 3 figures, accepted for publication in Phys. Rev. Let

Perception and Language: Using the Rorschach with People with Aphasia

This study explored the use of the Rorschach with eight individuals diagnosed with mild to moderate fluent or non-fluent types of aphasia to consider the extent to which the Rorschach captured aspects of language impairment not otherwise probed by traditional neurolinguistic measures. A ninth participant, with Wernicke’s aphasia, produced non-scorable responses and was therefore left out of all analyses. Of primary interest was whether the Rorschach, historically understood as a projective psychological instrument, would allow individuals living with language impairment to recognize, retrieve and coherently express words that reflected their thoughts. At the same time, this study sought to explore how the ambiguous nature of Rorschach inkblots could be leveraged together with traditional neuropsychological and linguistic measures, to provide insight into the relationship between perception, thought, psychological process and language - a multimethod assessment approach to describe the complex phenomena surrounding aphasia. This study demonstrated that individuals with reduced language function were able to provide responses to inkblots presented in a Rorschach assessment that were sufficient in number and quality to allow scoring and interpretation. Spearman’s rank-order correlation coefficients were calculated for WAB-R AQ score, CLQT Language Functions Domain Scores, the Rorschach cognitive processing simplicity, complexity scores and, the thought and perception EII and severe cognitive scores. Correlations among neurolinguistic and Rorschach cognitive processing and thought and perception variables, indicate a clear and intuitive relationship between these different measures. Finally, participants were administered a confrontation naming task in which a series of 10 black and white line drawings representing images of the most popular responses for each of the 10 Rorschach cards were presented. Results from that task confirmed that study participants could accurately retrieve the word for the most common responses, suggesting that object naming is not a limitation in the population of individuals with mild to moderate aphasia. Although differences between small groups of individuals with fluent and non-fluent aphasia could not be validated with significance testing, descriptive analyses showed some differences in means and standard deviations of Rorschach variable scores between the two groups. Specifically, individuals in the non-fluent aphasia group, who had more impairment in language ability, provided more vague responses, were typically only able to provide one defining characteristic of the blot (i.e., blends), and produced more communicative distortions (as measured by the thought and perception variables) than compared to individuals in the fluent aphasia group. The participant group, as a whole, produced a high degree of vague responses, was found to produce more simplistic descriptions of the blot, and typically only produced one defining characteristic of the blot (i.e., blends) - as compared to the neurotypical population. This study shows that the Rorschach can be administered to a population of individuals with mild to moderate fluent or non-fluent aphasia to generate scoreable results, with named objects comparable to those in norms derived from a neurotypical population. Limited amount and quality of supporting description of those named objects provided by the participants, however, limits the utility of the Rorschach from a psychological assessment perspective. In light of the dependence of this instrument on verbal ability, future studies might consider modified application of the Rorschach with administration that allows non-verbal responses (e.g., drawing, picture taking) as a means of supplementing participant verbal responses – to develop a richer understanding of the individual’s perception, and insight into their psychological state

Measuring microwave quantum states: tomogram and moments

Two measurable characteristics of microwave one-mode photon states are discussed: a rotated quadrature distribution (tomogram) and normally/antinormally ordered moments of photon creation and annihilation operators. Extraction of these characteristics from amplified microwave signal is presented. Relations between the tomogram and the moments are found and can be used as a cross check of experiments. Formalism of the ordered moments is developed. The state purity and generalized uncertainty relations are considered in terms of moments. Unitary and non-unitary time evolution of moments is obtained in the form of linear differential equations in contrast to partial differential equations for quasidistributions. Time evolution is specified for the cases of a harmonic oscillator and a damped harmonic oscillator, which describe noiseless and decoherence processes, respectively.Comment: 10 pages, 1 figure, to appear in Phys. Rev.

POD-Galerkin advection model for convective flow Application to a flapping rectangular supersonic jet

International audienceThis article describes a model obtained by applying Proper Orthogonal Decomposition to the ad-vection equation. The resulting set of equations links the POD modes, their temporal and spatial derivatives and the flow convection velocity. It provides a technique to calculate the convection velocity of coherent structures. It follows, from the model, that a priori knowledge of the convection velocity suffices to construct a dynamical model of the flow. This is demonstrated using experimental data

Sr 2 IrO 4 magnetic phase diagram, from resistivity

International audienceWe show that the transition to the antiferromagnetic state in zero magnetic field does show up in the transverse resistivity, for which we point out the possibility for a direct spin orientation effect. In an applied field, we propose that the transition is split into two lines, corresponding to in-plane and out-of-plane magnetic ordering. This picture is corroborated by transverse magnetization measurements. The magnetic phase diagram for Sr2IrO4 was investigated, using the angular dependence of the resistivity transverse to the IrO2 planes