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Compound La0.7Sr0.3Mn0.85Nb0.15O3, in which manganese ions are in an oxidation state close to 3+, are studied by neutron diffraction and magnetic measurements. This compound is shown to be a ferromagnet with T C = 145 K and a magnetic moment of 3.1 μB/Mn at T = 10 K. No signs of cooperative orbital ordering are detected. When Mg2+ ions substitute for some Nb5+ ions, Mn4+ ions appear but ferromagnetism is not enhanced. An increase in the structural distortions leads to a decrease in the ferromagnetic component. The ferromagnetic state is assumed to be caused by substantial hybridization of the e g orbitals of manganese and oxygen, which increases the positive part of the superexchange interactions.

Structural and magnetization measurements have been performed on the La0.7Sr0.3Mn0.85 Nb 0.15 - x 5 + Mg x 2 + O3 stoichiometric compounds. With rise of the Mg2+ content the formal oxidation state manganese increases from +3 ( x = 0 ) up to +3.55 ( x = 0.15 ) . The compositions with 0 ⩽ x ≤ 0.08 undergo a structural transition from rhombohedral to orthorhombic symmetry below room temperature whereas x = 0.1 and x = 0.15 compounds are rhombohedral down to 2 K. The structural parameters evidence that the orthorhombic phase is not long-range orbitally ordered and that the structural transition is associated with a steric effect. The Mg-free compound is ferromagnetic with the Curie point of around 150 K and a magnetic moment of 3.1 μ B /Mn. The substitution of Nb5+ with Mg2+ leads to a gradual weakening of the ferromagnetic component while in the x = 0.15 compound A-type antiferromagnetic short-range order is stabilized in spite of macroscopic R 3 ¯ c symmetry. All the compositions show insulating behavior. It is suggested that ferromagnetism is originated from superexchange interactions via oxygen. Covalence enhances the positive part of the superexchange interactions whereas structural disorder induced by Nb5+ and Mg2+ ions leads to suppression of ferromagnetism.

International audience; This article is devoted to the thermal expansion of ZnSb combining experiments (neutron and X-ray) andcalculations based on density functional theory. Related properties are also studied such as: the zone-center(Raman and infrared) phonon modes, the dielectric (electronic and static) tensors, the phonondensity-of-states, the specific heats and the isotropic atomic displacement parameters. Our experimentaldata show highly anisotropic thermal expansion with large values along the a-direction. Concomitantly,a large increase of the Zn–Zn intra-ring distances and of one of the intra-ring Zn–Sb distances isobserved, while other interatomic distances do not significantly change. In agreement with ourcalculations, the thermal expansion has positive values along the three crystal directions except around30 K where it has weak negative values along the b and c-directions. This anomalous expansion is moreimportant along the c-direction and it is mainly due to phonon modes with frequencies up to 75 cm1.These modes are located in the S–Y–G (resp. G–Z) q-point range along the b (resp. c) direction. Phononmodes located in the G–X and in the Y–G–Z q-point range with frequencies up to 175 cm1 areresponsible for the positive large thermal expansion at room temperature along the a-direction. Themuch reduced anisotropy of the thermal conductivity is related to the lower Debye temperatures alongthe b and c-directions and mainly to the small transverse sound velocity between these directions.

Anion-deficient La0.5Ba0.5CoO2.8 and Y0.25Ca0.25Sr0.5CoO2.62 cobaltites are studied under pressures up to 6.5 GPa in the temperature range of 5−300 K by neutron powder diffraction. Under ambient pressure both compounds are antiferromagnetic with TN = 250 K. The applied pressure induces in the first compound a gradual transition from the antiferromagnetic to ferromagnetic state through a mixed magnetic state, whereas the second compound remains antiferromagnetic in the whole pressure range. We suggest that the magnetic ground state depends on the unit-cell volume and the magnetic transition is associated with the transition of cobalt ions from the mixed high-spin/low-spin state to the intermediate-spin/low-spin state.

We report on the determination of the full magnetic structure of ${\mathrm{Tb}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$ including the Ir sublattice by means of powder neutron diffraction. Below ${T}_{N}\ensuremath{\sim}125\phantom{\rule{0.28em}{0ex}}\mathrm{K}$, both the Tb and the Ir sublattices order in a so-called all-in/all-out magnetic structure. However, additional magnetic intensity appears below 10 K on the (111) reflection indicating a change in the magnetic structure. We were able to describe the low-temperature magnetic structure with an additional $XY$ component on the Tb sublattices. The moment sizes at 1.5 K amount to $0.55(3){\ensuremath{\mu}}_{B}/\mathrm{Ir}$ and $5.22(3){\ensuremath{\mu}}_{B}/\mathrm{Tb}$. The ${\mathrm{Tb}}^{3+}$ moments are titled about ${6}^{\ensuremath{\circ}}$ off from the [111] direction. Moreover, it was found that the Tb moments couple antiferromagnetically with their six nearest-neighboring Ir moments below ${T}_{N}$. This is in contrast to the case of ${\mathrm{Nd}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$. The ${\mathrm{Ir}}^{4+}$ moment sizes of ${\mathrm{Tb}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$ are larger than that of ${\mathrm{Nd}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$ indicating that hybridization effects between the Ir $5d$ and the O $2p$ orbitals are smaller in ${\mathrm{Tb}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$.

The influence of external pressure (P ⩽ 5 GPa) on both the structural and magnetic ordering in MnV

We introduce the concept of trajectory-specific sensory manifolds. They are the unique multidimensional and time-varying combinations of afferent signals that obligatorily emerge during a limb movement. We use the example of muscle spindles (i.e., the muscle's proprioceptors for length and velocity) that arise during movements of an arm (a planar 2-DOF 6-muscle model) during the production of straight, curved and oscillatory hand movements. Through the use of parallel coordinates, we visualize the high-dimensional evolution of the afferent signaling across muscles and tasks. We demonstrate that a given movement gives rise to a distinct sensory manifold embedded in the 12-D space of spindle information that is largely independent of the choice of muscle coordination strategy. Given that muscle lengths and velocities are fully determined by joint kinematics, such manifolds provide a rich set of information to use in its control.

The development of short- and long-range magnetic order induced in a frustrated zig-zag ladder compound SrDy2O4 by an applied field is studied using neutron diffraction techniques. In zero field, SrDy2O4 lacks long-range magnetic order down to temperatures as low as 60 mK, and the observed powder neutron diffraction (PND) patterns are dominated by very broad diffuse scattering peaks. Single crystal neutron diffraction reveals that the zero-field magnetic structure consists of a collection of antiferromagnetic chains running along the c axis and that there is very little correlation between the chains in the ab plane. In an applied magnetic field, the broad diffuse scattering features in PND are gradually replaced by much sharper peaks, however, the pattern remains rather complex, reflecting the highly anisotropic nature of SrDy2O4. Single crystal neutron diffraction shows that a moderate field applied along the b axis induces an up-up-down magnetic order associated with a 1/3-magnetisation plateau, in which magnetic correlation length in the ab plane is significantly increased, but it nevertheless remains finite. The resolution limited k = 0 peaks associated with a ferromagnetic arrangement appear in powder and single crystal neutron diffraction patterns in fields of 2.5 T and above.

Purpose Research suggests that there are reciprocal relationships between mental health (MH) disorders and epilepsy risk. However, MH relationships to post-traumatic epilepsy (PTE) have not been explored. Thus, the objective of this study was to assess associations between PTE and frequency of depression and/or anxiety in a cohort of individuals with moderate-to-severe TBI who received acute inpatient rehabilitation. Methods Multivariate regression models were developed using a recent (2010–2012) cohort (n = 867 unique participants) from the TBI Model Systems (TBIMS) National Database, a time frame during which self-reported seizures, depression [Patient Health Questionnaire (PHQ)-9], and anxiety [Generalized Anxiety Disorder (GAD-7)] follow-up measures were concurrently collected at year-1 and year-2 after injury. Results PTE did not significantly contribute to depression status in either the year-1 or year-2 cohort, nor did it contribute significantly to anxiety status in the year-1 cohort, after controlling for other known depression and anxiety predictors. However, those with PTE in year-2 had 3.34 times the odds (p = .002) of having clinically significant anxiety, even after accounting for other relevant predictors. In this model, participants who self-identified as Black were also more likely to report clinical symptoms of anxiety than those who identified as White. PTE was the only significant predictor of comorbid depression and anxiety at year-2 (Odds Ratio 2.71; p = 0.049). Conclusions Our data suggest that PTE is associated with MH outcomes 2 years after TBI, findings whose significance may reflect reciprocal, biological, psychological, and/or experiential factors contributing to and resulting from both PTE and MH status post-TBI. Future work should consider temporal and reciprocal relationships between PTE and MH as well as if/how treatment of each condition influences biosusceptibility to the other condition.

Trabajo presentado como póster al Joint European Magnetic Symposia (JEMS 2012) celebrado en Parma (Italia) del 9 al 14 de septiembre de 2012., This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, The magnetic properties of the double perovskite Tb2MnCoO6 have been studied. The refinement of neutron pattern reveals antisite defects in the ordered array of Mn4+ and Co2+ cations. The temperature dependence of dc magnetization exhibits a magnetic transition at ~100 K with a strong irreversibility between ZFC and FC conditions. The ac magnetic susceptibility curve shows a strong peak at the same temperature whose position and intensity slightly depends on the field frequency. These features are typical of a spin-glasslike phase but neutron diffraction shows the onset of a ferromagnetic contribution at the same temperature. Ferromagnetism in this sample is associated to superexchange interaction between Mn4+ and Co2+ cations. The most striking property of Tb2MnCoO6 is the presence of field induced transitions. This is observed in the magnetic hysteresis loops below 100K. The metamagnetic transition was studied by powder neutron diffraction at different temperatures and magnetic fields. At low temperature, the magnetic field induces a long range magnetic ordering of Tb3+ moments in the ab-plane. The magnetic peaks of Tb moments at 30 kOe vanish at 60K. Above this temperature, the metamagnetic transition is ascribed to the field induced transition from short to long range ferromagnetic ordering in the Mn-Co sublattice., This work was supported by MICINN (project, FIS08-03951, MAT2007-61621) and DGA (CAMRADS).

Background. The Intentional Relationship Model (IRM) proposes six therapeutic modes as ways of relating to clients. The Norwegian self-efficacy for therapeutic mode use (N-SETMU) was found to have a one-component structure. However, its items reflect abstract concepts rather than concrete behaviors. Aim. To validate further the N-SETMU by linking its items to the Norwegian client assessment of modes (N-CAM), with 30 items constituting six scales (linked to each mode), possessing concrete, behavioral content. Methods. Occupational therapy students (n=111) completed the N-SETMU and the N-CAM derived items, along with sociodemographic information. Component structure was analyzed with Principal Components Analysis (PCA), internal consistency of scales with Cronbach’s α, and associations between scale scores with Pearson’s r. Results. All items on all N-CAM derived scales loaded on one latent component, except one item related to problem-solving. After removing this item, the scale functioned appropriately. Cronbach’s α for all N-CAM derived scales ranged 0.88–0.94, and the associations between the N-CAM derived scales and the corresponding N-SETMU items ranged between 0.60 (advocating) and 0.79 (encouraging). Conclusions. In view of the strong associations between the concrete, N-CAM derived scales and the abstract N-SETMU items, this study supports the concurrent validity of the N-SETMU.

This dataset is supplementary to the article of Ritter et al. (2017). In this article, a new experimental device is presented that facilitates precise measurements of boundary forces and surface deformation at high temporal and spatial resolution. This supplementary dataset contains the measurement data from two experiments carried out in this new experimental device: one experiment of an accretionary critical wedge and one of Riedel-type strike-slip deformation. For a detailed description of the set-up and an analysis of the data, please see Ritter et al. (2017). The data available for either experiment are: • A video showing deformation in top view together with the evolution of boundary force. This file is in AVI-format. • A time-series of 2D vector fields describing the surface deformation. These vector fields were obtained from top-view video images of the respective experiment by means of digital image correlation (DIC). Each vector field is contained in a separate file; the files are consecutively numbered. The vector fields are stored in *.mat-files that can be opened using e.g. the software Matlab or the freely available GNU Octave. They take the form of Matlab structure arrays and are compatible to the PIVmat-toolbox by Moisy (2016) that is freely available. The most important fields of the structure are: x and y, that are vectors spanning a coordinate system, and vx and vy, which are arrays containing the actual vector components in x- and y-direction, respectively. • A file containing the measurements of the boundary force applied to drive deformation. This file is also a *.mat-file, containing a structure F with fields force, velocity and position. These fields are vectors describing the force applied by the indenter, the indenter velocity and the indenter position

[1] Magma transfer, i.e., dike propagation, is partly controlled by Young's modulus (elasticity) contrasts (ratio upper layer to lower layer modulus) in the host rock. Here we try to better constrain the elasticity contrasts controlling the propagation velocity of dikes and their arrest. We simulate dike propagation in layered elastic media with different elasticity contrasts. Salted gelatin and water represent host rock and magma, respectively. For common density ratios between magma and host rock (~1.1), velocity variations are observed and a critical threshold in the elasticity contrast between layers results in the Young's modulus ratio of 2.1 ± 0.6. Naturally occurring elasticity contrasts can be much higher than this experimental threshold, suggesting that dike arrest due to heterogeneous elastic host rock properties is more frequent than expected. Examples of recently deflected or stalled dikes inside volcanoes and the common presence of high-velocity bodies below volcanoes suggest that better defining elasticity contrasts below volcanoes helps in forecasting eruptions.

Purpose of review The introduction of endovascular techniques and improvements in the medical management of atherosclerotic carotid lesions have led to changes in the modern management of stroke. The purpose of this review is to summarize the latest developments in surgical carotid intervention and highlight the current controversies. Recent findings The predominant controversies that dominate the correct surgical management of carotid atherosclerotic disease are: Notwithstanding the results of the Carotid Revascularisation Endarterectomy versus Stenting Trial, does carotid artery stenting produce equivalent outcomes to surgical carotid endarterectomy? Should recent developments in best medical management of these lesions and changing socioeconomic factors restrict the indication for surgical intervention for asymptomatic lesions? What is the ideal time frame for carotid interventions in symptomatic patients? Summary There is insufficient current or historic evidence to resolve these controversies and further large randomized controlled trials are therefore required. The current knowledge limits are explored.

Background Longitudinal studies of experimental pain are rare and little is known about the differences regarding sensitization and habituation over longer periods in patients with chronic pain or depression compared with controls. Methods We used a standardized longitudinal painful heat paradigm that was designed to induce long-term habituation in 19 patients with chronic low back pain (CLBP), 21 patients with depression (DEP) and 21 healthy participants (controls) over a time course of eight consecutive days. We applied functional magnetic resonance imaging on the first and last day of this period and after 3 months. Results Although the pain paradigm was standardized, patients with DEP exhibited significantly higher pain thresholds and a trend to higher pain ratings and, in functional imaging, showed less activation of the operculum and the secondary somatosensory cortex (S2) as compared to patients with CLBP and controls. Conversely, patients with CLBP showed increased activation in the anterior insula and parietal operculum as compared to patients with DEP and controls. Within session, all participants sensitized to pain, which was associated with higher activation levels in the thalamus, amygdala, midcingulate cortex, and sensory and motor areas. However, patients with depression showed significantly less activation in midbrain and brainstem areas. Conclusion Given that pain and depression potentiate each other clinically, our data suggest that this may involve different cortical pain areas.

Background: Multiparameter flow cytometry is a useful tool for the diagnostic evaluation of mature B-cell neoplasms (MBN). Recently, it has been shown that CD200 may improve the distinction between chronic lymphocytic leukemia (CLL; CD200+) and mantle cell lymphoma (MCL; CD200-), but the role of CD200 expression in atypical CLL and other MBN remains to be established. Methods: To address this issue, we investigated the expression of CD200 in 159 consecutive cases of MBN. Results: CD200 was strongly expressed in CLL and was revealed to be an excellent marker to distinguish CLL from MCL, even in cases of atypical CLL. However, lack of CD200 was not an exclusive finding of MCL, being also observed in other MBNs. Furthermore, CD200 was highly expressed in hairy cell leukemia, being useful in the differential diagnosis of lymphomas with villous lymphocytes. Herein, we propose an algorithm to classify CD5+ MBNs based on the expression of CD200, CD11c, heavy chain immunoglobulins and Matutes score. Conclusions: These results expand the understanding of the CD200 expression in MBNs, giving further support for the inclusion of this marker in the routine investigation by flow cytometry. © 2013 Clinical Cytometry Society.

Neutron diffraction studies of the La0.5Ba0.5CoO2.8 at the different temperatures has been performed. This solid solution crystallizes in the cubic structure (Pm3m space group) and exhibits below TN ~ 250K G-type antifferomagnetic ordering. Applied pressure suppresses magnetic ordering. Anomalous changes of the lattice parameters under pressure have been found.

Among others, pyrochlore iridates with strong spin-orbit coupling have received attention recently due to the prediction of Weyl semimetal states in these materials. Despite tremendous efforts, there exists no direct measurement of the spin structure at the iridium site by means of neutron diffraction. This might be caused by the small ordered Ir moment and also by the neutron absorbing properties of the Ir ions. Up to now, only basic indirect evidence for the spin structure at the iridium site exists. From the observation here of the full magnetic structure of Nd${}_{2}$Ir${}_{2}$O${}_{7}$ via neutron diffraction experiments, the authors obtain direct insight into unknown aspects of the physics of the iridium ions in pyrochlore iridates.

SummaryObjective Determine incidence of posttraumatic seizure (PTS) following traumatic brain injury (TBI) among individuals with moderate-to-severe TBI requiring rehabilitation and surviving at least 5 years. Methods Using the prospective TBI Model Systems National Database, we calculated PTS incidence during acute hospitalization, and at years 1, 2, and 5 postinjury in a continuously followed cohort enrolled from 1989 to 2000 (n = 795). Incidence rates were stratified by risk factors, and adjusted relative risk (RR) was calculated. Late PTS associations with immediate ( 7 day) versus no seizure prior to discharge from acute hospitalization was also examined. Results PTS incidence during acute hospitalization was highest immediately (

The magnetic structure of the mixed rare-earth system Pr x Y1-x Fe3(BO3)4 (x = 0.75, 0.67, 0.55, 0.45, 0.25) was studied via magnetic and resonance measurements. These data evidence the successive spin reorientation from the easy-axis antiferromagnetic structure formed in PrFe3(BO3)4 to the easy-plane one of YFe3(BO3)4 associated with the weakening of the magnetic anisotropy of the Pr subsystem due to its diamagnetic dilution by nonmagnetic Y. This reorientation occurs through the formation of an inclined magnetic structure, as was confirmed by our previous neutron research in the range of x = 0.67 ÷ 0.45. In the compounds with x = 0.75 and 0.67 whose magnetic structure is close to the easy-axis one, a two-step spin reorientation takes place in the magnetic field H||c. Such a peculiarity is explained by the formation of an interjacent inclined magnetic structure with magnetic moments of Fe ions located closer to the basal plane than in the initial state, with these intermediate states remaining stable in some ranges of the magnetic field. An approach based on a crystal field model for the Pr(3+) ion and the molecular-field approximation is used to describe the magnetic characteristics of the system Pr x Y1-x Fe3(BO3)4. With the parameters of the d-d and f-d exchange interactions, of the magnetic anisotropy of the iron subsystem and of the crystal field parameters of praseodymium thus determined, it is possible to achieve a good agreement between the experimental and calculated temperature and field dependences of the magnetization curves (up to 90 kOe) and magnetic susceptibilities (2-300 K).

Despite the arsenal of technologies employed to control foodborne nontyphoidal Salmonella (NTS), infections have not declined in decades. Poultry is the primary source of NTS outbreaks, as well as the fastest growing meat sector worldwide. With recent FDA rules for phasing-out antibiotics in animal production, pressure is mounting to develop new pathogen reduction strategies. We report on a technology to reduce Salmonella enteritidis in poultry. We engineered probiotic E. coli Nissle 1917, to express and secrete the antimicrobial peptide, Microcin J25. Using in vitro experiments and an animal model of 300 turkeys, we establish the efficacy of this technology. Salmonella more rapidly clear the ceca of birds administered the modified probiotic than other treatment groups. Approximately 97% lower Salmonella carriage is measured in a treated group, 14 days post-Salmonella challenge. Probiotic bacteria are generally regarded as safe to consume, are bile-resistant and can plausibly be modified to produce a panoply of antimicrobial peptides now known. The reported systems may provide a foundation for platforms to launch antimicrobials against gastrointestinal tract pathogens, including ones that are multi-drug resistant.

Summary Objective Posttraumatic seizures (PTS) commonly occur following severe traumatic brain injury (sTBI). Risk factors for PTS have been identified, but variability in who develops PTS remains. Excitotoxicity may influence epileptogenesis following sTBI. Glutamate transporters manage glutamate levels and excitatory neurotransmission, and they have been associated with both epilepsy and TBI. Therefore, we aimed to determine if genetic variation in neuronal glutamate transporter genes is associated with accelerated epileptogenesis and increased PTS risk after sTBI. Methods Individuals (N = 253) 18–75 years of age with sTBI were assessed for genetic relationships with PTS. Single nucleotide polymorphisms (SNPs) within SLC1A1 and SLC1A6 were assayed. Kaplan-Meier estimates and log-rank statistics were used to compare seizure rates from injury to 3 years postinjury for SNPs by genotype. Hazard ratios (HRs) were estimated using Cox proportional hazards regression for SNPs significant in Kaplan-Meier analyses adjusting for known PTS risk factors. Results Thirty-two tagging SNPs were examined (SLC1A1: n = 28, SLC1A6: n = 4). Forty-nine subjects (19.37%) had PTS. Of these, 18 (36.7%) seized within 7 days, and 31 (63.3%) seized between 8 days and 3 years post-TBI. With correction for multiple comparisons, genotypes at SNP rs10974620 (SLC1A1) were significantly associated with time to first seizure across the full 3-year follow-up (seizure rates: 77.1% minor allele homozygotes, 24.8% heterozygotes, 16.6% major allele homozygotes; p = 0.001). When seizure follow-up began day 2 postinjury, genotypes at SNP rs7858819 (SLC1A1) were significantly associated with PTS risk (seizure rates: 52.7% minor allele homozygotes, 11.8% heterozygotes, 21.1% major allele homozygotes; p = 0.002). After adjusting for covariates, we found that rs10974620 remained significant (p = 0.017, minor allele versus major allele homozygotes HR 3.4, 95% confidence interval [CI] 1.3–9.3). rs7858819 also remained significant in adjusted models (p = 0.023, minor allele versus major allele homozygotes HR 3.4, 95%CI 1.1–10.5). Significance Variations within SLC1A1 are associated with risk of epileptogenesis following sTBI. Future studies need to confirm findings, but variation within neuronal glutamate transporter genes may represent a possible pharmaceutical target for PTS prevention and treatment.

At 300 K (La0.375Ca0.625)MnO3 crystallizes in the orthorhombic Pnma space group; on cooling a Pnma → Pnma structural transition occurs due to charge-orbital ordering within the Mn sub-lattice, producing a superstructure consistent with a Wigner-crystal model with a tripling of the cell parameter a. The primary active mode yielding the observed ordered structure corresponds to the irreducible representation labelled Σ 3 , with wave vector (⅓,0,0). Nevertheless, the disordered polymorph stable at room temperature is retained at low temperature as a secondary phase, coexisting with the charge-orbital ordered structure. These two phases display different spin orderings; the antiferromagnetic structure associated to the charge-orbital ordered phase is characterized by a magnetic propagation wave vector k=(0,0,½), with a canted spin ordering in the ac plane, whereas a Cy-type arrangement develops within the disordered polymorph.

R. Reifarth et al: ; 12 págs.; 9 figs.; Open Access funded by Creative Commons Atribution Licence 3.0 ; Nuclear Physics in Astrophysics VI (NPA6), The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process ow and r-process -decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will oer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes., This project was supported by the HGF Young Investigators Project VH-NG-327, EMMI, H4F, HGS-HIRe, JINA, NAVI, DFG and ATHENA.

Nitration of o-xylene in the presence of fuming nitric acid and a combination of 115 % polyphosphoric acid, nitrobenzene, and H-Y zeolite catalyst provides a selectivity of 4-nitro-o-xylene of 71 at 85 mol% conversion of o-xylene. The present process has the potential to be an environmentally-friendly, sustainable, safe, and selective aromatic nitration process compared to the incumbent process.

We are living in an era of unprecedented change in academic, industrial, and government-based research worldwide, and navigating these rough waters requires “all hands on deck”. Toward this end, Organometallics has assembled a panel of seventeen experts who share their thoughts on a variety of matters of importance to our field. In constituting this panel, an attempt was made to secure representation from a number of countries and career stages, as well as from industry. We were fortunate that so many busy experts could take the time to spend with us. The following pages constitute an edited transcript of the panel discussion held on August 29, 2011, which was structured around the 10 questions summarized in the side bar and repeated below.

Glutamate is the neurotransmitter responsible for fast excitatory transmission from vagal afferents to second order neurons in the NTS. Antagonism of NMDA-type glutamate receptors in the NTS increases food intake and attenuates reduction of food intake by vagally mediated satiation signals, such as cholecystokinin. Although, the cellular location(s) of NMDA receptors that participate in satiation is uncertain, recent findings suggest that attenuation of satiation by NMDA receptor antagonists is due, at least in part, to their action on primary vagal afferents themselves. While evidence is accumulating that NMDA receptors located on vagal afferent endings in the hindbrain are involved in control of food intake, there also is preliminary evidence that peripheral NMDA receptors also may influence vagal control of food intake. Hence, NMDA receptor expression on central and perhaps peripheral vagal afferent endings could provide a parsimonious mechanism for modulation of satiation signals by endogenously released glutamate.

Intraperitoneal injection of CCK reduces food intake and triggers a behavioral pattern similar to natural satiation. Reduction of food intake by CCK is mediated by vagal afferents that innervate the stomach and small intestine. These afferents synapse in the hindbrain nucleus of the solitary tract (NTS) where gastrointestinal satiation signals are processed. Previously, we demonstrated that intraperitoneal (IP) administration of either competitive or noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonists attenuates reduction of food intake by CCK. However, because vagal afferents themselves express NMDA receptors at both central and peripheral endings, our results did not speak to the question of whether NMDA receptors in the brain play an essential role in reduction of feeding by CCK. We hypothesized that activation of NMDA receptors in the NTS is necessary for reduction of food intake by CCK. To test this hypothesis, we measured food intake following IP CCK, subsequent to NMDA receptor antagonist injections into the fourth ventricle, directly into the NTS or subcutaneously. We found that either fourth-ventricle or NTS injection of the noncompetitive NMDA receptor antagonist MK-801 was sufficient to inhibit CCK-induced reduction of feeding, while the same antagonist doses injected subcutaneously did not. Similarly fourth ventricle injection of d-3-(2-carboxypiperazin-4-yl)-1-propenyl-1-phosphoric acid (d-CPPene), a competitive NMDA receptor antagonist, also blocked reduction of food intake following IP CCK. Finally, d-CPPene injected into the fourth ventricle attenuated CCK-induced expression of nuclear c-Fos immunoreactivity in the dorsal vagal complex. We conclude that activation of NMDA receptors in the hindbrain is necessary for the reduction of food intake by CCK. Hindbrain NMDA receptors could comprise a critical avenue for control and modulation of satiation signals to influence food intake and energy balance.

The physical and structural properties of Fe1.11Te and Fe1.11Te0.5Se0.5 have been investigated by means of X-ray and neutron diffraction as well as physical property measurements. For the Fe1.11Te compound, the structure distortion from a tetragonal to monoclinic phase takes place at 64 K accompanied with the onset of antiferromagnetic order upon cooling. The magnetic structure of the monoclinic phase was confirmed to be of antiferromagnetic configuration with a propagation vector k = (1/2, 0, 1/2) based on Rietveld refinement of neutron powder diffraction data. The structural/magnetic transitions are also clearly visible in magnetic, electronic and thermodynamic measurements. For superconducting Fe1.11Te0.5Se0.5 compound, the superconducting transition with T c = 13.4 K is observed in the resistivity and ac susceptibility measurements. The upper critical field H c2 is obtained by measuring the resistivity under different magnetic fields. The Kim’s critical state model is adopted to analyze the temperature dependence of the ac susceptibility and the intergranular critical current density is calculated as a function of both field amplitude and temperature. Neutron diffraction results show that Fe1.11Te0.5Se0.5 crystalizes in tetragonal structure at 300 K as in the parent compound Fe1.11Te and no structural distortion is detected upon cooling to 2 K. However an anisotropic thermal expansion anomaly is observed around 100 K.

Application of the “chimney” stent technique is described in a case of complex multilevel atherosclerotic disease involving the juxtarenal aorta. A patient with significant comorbidities was unsuitable for major open reconstructive surgery. He was treated with a combined procedure consisting of chimney stent placement in the juxtarenal aorta, iliac “kissing” stent placement, and right-sided common femoral artery (CFA) replacement. This case shows that the chimney stent technique can be a feasible alternative to leaving a safety wire in the renal arteries and observation during primary angioplasty in complex atherosclerotic lesions of the abdominal aorta.