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Static stripe order is detrimental to superconductivity. Yet, it has been proposed that transverse stripe fluctuations may enhance the inter-stripe Josephson coupling and thus promote superconductivity. Direct experimental studies of stripe dynamics, however, remain difficult. From a strong-coupling perspective, transverse stripe fluctuations are realized in the form of dynamic "kinks"-sideways shifting stripe sections. Here, we show how modest uniaxial pressure tuning reorganizes directional kink alignment. Our starting point is La

It is well established that in the low-temperature limit, the two-dimensional quantum Heisenberg antiferromagnet on a square lattice (2DQHAFSL) exhibits an anomaly in its spectrum at short-wavelengths on the zone-boundary. In the vicinity of the [Formula: see text] point the pole in the one-magnon response exhibits a downward dispersion, is heavily damped and attenuated, giving way to an isotropic continuum of excitations extending to high energies. The origin of the anomaly and the presence of the continuum are of current theoretical interest, with suggestions focused around the idea that the latter evidences the existence of spinons in a two-dimensional system. Here we present the results of neutron inelastic scattering experiments and Quantum Monte Carlo calculations on the metallo-organic compound Cu(DCOO)[Formula: see text]D

Summary Airborne electromagnetics (AEM) has successfully mapped and characterised groundwater systems in a range of landscapes and geological settings in the East Kimberley Region of north-western Australia. The AEM data enabled rapid imaging of key elements of hydrogeological systems in near-surface Cenozoic paleovalley, alluvial fan and colluvial sediments, and in underlying tectonically-inverted sedimentary basins. Rapid mapping and assessment of groundwater systems, MAR targets and salinity hazards involved the integration of AEM data with Ground Magnetic Resonance (GMR), seismic reflection, drilling and pump tests, borehole geophysics, soils, regolith, geological and structural mapping, and hydrogeological and hydrochemical investigations. AEM survey design was aided by the use of spatio-temporal analysis of Landsat data to identify areas of potential surface-groundwater interaction. A suite of equivalent 1D AEM inversion models produced comparable images of the sub-surface hydrostratigraphy and faults. However, 2.5D inversions produced different solutions in key locations. 3D inversions were subsequently performed, and drilling and tectonic analysis was used to assess all AEM inversion models. Recognising zones of structural complexity was important in the successful development of appropriate AEM inversion strategies and models. Overall, the success of groundwater system mapping has been due to the use of AEM within a broader, inter-disciplinary, multi-physics project framework.

Experience over the past 15 years has demonstrated that the use of airborne electromagnetics (AEM) for near-surface hydrogeological investigations often requires high resolution data to map key functional elements of the hydrogeological system. In the Broken Hill Managed Aquifer Recharge (BHMAR) project, the AEM acquisition strategy was governed by the need to rapidly identify and assess a number of potential managed aquifer recharge (MAR) and groundwater resource targets over a large area (>7,500 km2) of the Lower Darling Valley, with a high degree of confidence, and in very short timeframes. A flight line spacing of 200-300m successfully mapped the key elements of the hydrostratigraphy, neotectonic features, and 14 potential MAR and groundwater targets. Subsequently, AEM data were re-inverted, enabling comparison of line spacing of 200 m, 600 m, 1 km, 2 km, 5 km and 10 km. Utilising the information gained from this exercise, a novel survey design was developed using a systems analysis approach incorporating a range of conceptual hydrogeological and geological models, morphotectonic and structural mapping, and temporal remote sensing and hydrogeological data. Trialling this approach, a few widely-spaced AEM transects identified potential new groundwater resources over a large area of the Middle- and Upper- Darling River Valley.

The spin dynamics of plate-shaped nanoparticles of NiO has been studied by inelastic neutron scattering and Mossbauer spectroscopy. A value of the in-plane anisotropy energy constant significantly larger than the bulk value has been measured. The temperature and field dependence of the energy of the antiferromagnetic resonance mode associated with this in-plane anisotropy has been studied. Both Mossbauer spectroscopy and neutron scattering data show that the magnetic fluctuations are strongly affected by the strength of interparticle interactions. (Some figures in this article are in colour only in the electronic version)

An electronically‐controlled, portable, cone penetrometer was designed, built, and tested. The penetrometer was driven electrically through a linear actuator. Cone position was sensed by a 10‐turn potentiometer, and force was sensed with an electronic load cell. A laptop computer controlled the linear actuator and recorded signals from the sensors through a data logger equipped with a serial interface. The penetrometer was capable of driving the cone at 0.84 cms‐1 (±5%) over a load range of 0 to 180 kg. The system allowed force and position excursion limits to be set through software and provided data sets at 1‐cm increments to depths of 45 cm and forces to 2,000 N. The penetrometer demonstrated good repeatability among closely spaced probings when force per unit cone area was plotted against depth.

The “re-invented triple-axis spectrometer (RITA) concept has existed for a decade. Recent developments at RITA-2 at PSI, have revealed more of the potential of this instrument class. We demonstrate the performance of the multi-blade imaging mode, which has been applied e.g. to studies of dispersion relations and emphasize the power of this mode in combination with the low background of RITA-2. In addition, we present other ways of utilizing the position sensitive detector in a RITA instrument. Simulations of a planned upgrade of the guide-monochromator system at RITA-2 have shown a potential to increase the flux at the sample position by a factor 5.

We present a combined magnetic neutron scattering and muon spin rotation study of the nature of the magnetic and superconducting phases in electronically phase separated La(2-x)Sr(x)CuO(4+y), x=0.04, 0.065, 0.09. For all samples, we find long-range modulated magnetic order below T(N) is approximately equal to Tc=39 K. In sharp contrast to oxygen-stoichiometric La(2-x)Sr(x)CuO(4), we find that the magnetic propagation vector as well as the ordered magnetic moment is independent of Sr content and consistent with that of the "striped" cuprates. Our study provides direct proof that superoxygenation in La(2-x)Sr(x)CuO(4+y) allows the spin stripe ordered phase to emerge and phase separate from superconducting regions with the hallmarks of optimally doped oxygen-stoichiometric La(2-x)Sr(x)CuO(4).

When the Fast Hankel Transform filter technique is used to calculate the dyadic multilayered Green's functions, it can be difficult to obtain accurate numerical results because of the branch-cut singularity and the surface wave poles singularity. The Modified Fast Hankel Transform filter algorithm is proposed to overcome this problem by expressing the Bessel function with a complex argument as a sum of terms of product of Bessel function with the real part of the argument and Bessel function with the imaginary part of the argument. Then the Fast Han-kel Transform filter technique is applied to each expansion term. Numerical results confirm that the proposed approach has high accuracy and efficiency and successfully extends the applicability of the conventional Fast Hankel Transform method to general multilayered geometries.

In high-temperature copper oxide superconductors, a novel magnetic order associated with the pseudogap phase has been identified in two different cuprate families over a wide region of temperature and doping. We report here the observation below 120 K of a similar magnetic ordering in the archetypal cuprate La(2-x)Sr(x)CuO4 (LSCO) system for x=0.085. In contrast with the previous reports, the magnetic ordering in LSCO is only short range with an in-plane correlation length of ∼10 A and is bidimensional (2D). Such a less pronounced order suggests an interaction with other electronic instabilities. In particular, LSCO also exhibits a strong tendency towards stripes ordering at the expense of the superconducting state.

Neutron diffraction is used to investigate the field-induced, antiferromagnetically ordered state in the two-leg spin-ladder material (Hpip)2CuBr4. This “classical” phase, a consequence of weak interladder coupling, is nevertheless highly unconventional: its properties are influenced strongly by the spin Luttinger-liquid state of the ladder subunits. We determine directly the order parameter (transverse magnetization), the ordering temperature, the spin structure, and the critical exponents around the transition. We introduce a minimal microscopic model for the interladder coupling and calculate the quantum fluctuation corrections to the mean-field interaction.

We present a neutron-scattering study of the static and dynamic spin correlations in the underdoped high-temperature superconductor YBa2Cu3O6.45 in magnetic fields up to 15 T. The field strongly enhances static incommensurate magnetic order at low temperatures and induces a spectral-weight shift in the magnetic-excitation spectrum. A reconstruction of the Fermi surface driven by the field-enhanced magnetic superstructure may thus be responsible for the unusual Fermi surface topology revealed by recent quantum-oscillation experiments.

Inelastic neutron-scattering experiments on the high-temperature superconductor La1.855Sr0.145CuO4 reveal a magnetic excitation gap Delta that decreases continuously upon application of a magnetic field perpendicular to the CuO2 planes. The gap vanishes at the critical field required to induce long-range incommensurate antiferromagnetic order, providing compelling evidence for a field-induced soft-mode driven quantum phase transition.

Here we present a combined study of the slightly underdoped novel pnictide superconductor Ba1-xKxFe2As2 by means of x-ray powder diffraction, neutron scattering, muon-spin rotation (microSR), and magnetic force microscopy (MFM). Static antiferromagnetic order sets in below T{m} approximately 70 K as inferred from the neutron scattering and zero-field-microSR data. Transverse-field microSR below Tc shows a coexistence of magnetically ordered and nonmagnetic states, which is also confirmed by MFM imaging. We explain such coexistence by electronic phase separation into antiferromagnetic and superconducting- or normal-state regions on a lateral scale of several tens of nanometers. Our findings indicate that such mesoscopic phase separation can be considered an intrinsic property of some iron pnictide superconductors.

We report the results of a combined muon-spin rotation and neutron-scattering study on La2-xSrxCuO4 in the vicinity of the so-called 1/8 anomaly. Application of a magnetic field drives the system toward a magnetically ordered spin-density-wave state, which is fully developed at 1/8 doping. The results are discussed in terms of competition between antiferromagnetic and superconducting order parameters.

It is easy to think of a journal as a firm entity, but the modus vivendi of a highly read journal such as CPT is quite the opposite. The launch of CPT Nature Network adds another dimension. Clinical Pharmacology & Therapeutics (2007) 82, 240-240. doi:10.1038/sj.clpt.6100315

Major advances in fundamental mechanisms underlying (patho)physiology over the past decades have generated a robust therapeutic armamentarium; exemplifi ed by synthetic hormones, multigenerational antibiotics, and recombinant vaccines, off ering eff ective interventions across a range of diseases. Th e exponential ascent of the new biology has transformed the comprehension of human health and disease and revolutionized technology; redefi ning clinical pharmacology in the context of discovery and translation, and the role of the clinical pharmacologist as the bridge between the laboratory and the patient, and thence to the population at large. Th e integration of cross-disciplinary concepts emerging from discovery and driving therapeutic solutions has imposed an evolutionary pressure on clinical pharmacology to focus on the identifi cation and application of tools for prognosis, prediction, cure, and, ultimately, prevention in pursuit of personalized medicine. Th e promise of clinical pharmacology and its impact on the future of therapeutics, in the emerging areas of combinatorial pharmacogenetics, targeted interference with disease, as well as stem cell–based tissue engineering and regeneration (to name a few), extends

Using polarized neutron scattering we establish that the magnetic order in La(1.48)Nd(0.4)Sr(0.12)CuO(4) is either (i) one dimensionally modulated and collinear, consistent with the stripe model or (ii) two dimensionally modulated with a novel noncollinear structure. The measurements rule out a number of alternative models characterized by 2D electronic order or 1D helical spin order. The low-energy spin excitations are found to be primarily transversely polarized relative to the stripe ordered state, consistent with conventional spin waves.

High-resolution neutron inelastic scattering experiments in applied magnetic fields have been performed on La1.895Sr0.105CuO4 (LSCO). In zero field, the temperature dependence of the low-energy peak intensity at the incommensurate momentum transfer QIC=(0.5,0.5+/-delta,0),(0.5+/-delta,0.5,0) exhibits an anomaly at the superconducting Tc which broadens and shifts to lower temperature upon the application of a magnetic field along the c axis. A field-induced enhancement of the spectral weight is observed, but only at finite energy transfers and in an intermediate temperature range. These observations establish the opening of a strongly downward renormalized spin gap in the underdoped regime of LSCO. This behavior contrasts with the observed doping dependence of most electronic energy features.

In the project RMT-monitoring funded by the European Union, a new radiomagnetotelluric device has been developed which can record time series of electric and magnetic fields in a wide frequency range from 10 kHz to 1 MHz. Transfer functions are determined by spectral analysis using a newly developed processing software. A workbench program has been developed in which the transfer functions are interpreted with conductivity models based on new inversion algorithms. The developed tensor radiomagnetotelluric device was tested in the laboratory and then applied successfully in the field to several environmental and groundwater problems in Russia, Ukraine, Denmark, Romania, and Germany. The observed transfer functions in the field are the first ones worldwide in the frequency above 250 kHz which leads to a better resolution of the shallow structure. The new device enables quick and efficient mapping of polluted areas and supports tensor measurements allowing a 2D or 3D interpretation of the field data.

High-resolution neutron scattering experiments on optimally doped La2-xSrxCuO4 (x=0.16) reveal that the magnetic excitations are dispersive. The dispersion is the same as in YBa2Cu3O6.85, and is quantitatively related to that observed with charge sensitive probes. The associated velocity in La2-xSrxCuO4 is only weakly dependent on doping with a value close to the spin-wave velocity of the insulating (x=0) parent compound. In contrast with the insulator, the excitations broaden rapidly with increasing energy, forming a continuum at higher energy and bear a remarkable resemblance to multiparticle excitations observed in 1D S=1/2 antiferromagnets. The magnetic correlations are 2D, and so rule out the simplest scenarios where the copper oxide planes are subdivided into weakly interacting 1D magnets.

Ground-based electromagnetic methods have for many years successfully been employed for hydrogeological investigations in Denmark. A wish for higher efficiency has led to a growing interest in the possibility of using airborne electromagnetic methods in the mapping campaign, and lately the helicopterborne electromagnetic frequency-domain (HEM) method has been in focus.

Transient electromagnetic (TEM) soundings have been used extensively in geophysical investigations in connection with environmental problems (Christensen and Sorensen 1998).

Geological forrnations may exhibit anisotropy in two ways. Firstly, forrnations like clay may be intrinsically anisotropic because of the micro-structure of the forrnation. Secondly, surface electric and electromagnetic methods have a limited resolution of the conductivity structure of the subsurface, and in one-dimensional modeling we shall often have to consider the collection of many thin layers as one composite layer, which will then be macro-anisotropic. In both cases it is most often assumed that the conductivity is the same in all horizontal directions, but different from the vertical conductivity. Neither galvanic nor inductive methods alone can resolve the anisotropy of the ground. However, a joint inversion of galvanic and inductive data requires that anisotropy be taken into account and can also resolve the coefficient of anisotropy and thereby contribute to a more detailed description of the subsurface resistivity structure (Jupp and Vozoff 1977). The deterrnination of electrical anisotropy is desirable as it may serve as an indicative parameter for the presence of otherwise unresolved thin layers. From a hydrogeological point of view these may severely influence the hydraulic flow pattern in the ground. Thin clay layers in an otherwise sandy forrnation will lower the vertical hydraulic conductivity considerably, and the presence of thin sand and gravel layers in an otherwise clayey forrnation may serve as fast hydraulic conduction channels for polluted water. In connection with mapping of raw materials anisotropy indicates that the material under investigation is not homogeneous throughout and may thus be of inferior quality. Through the following analyses it is found that a combined use of geoelectrical and transient soundings can resolve the coefficient of anisotropy of a subsurface layer. It is found that the coefficient of anisotropy is only well resolved for layers which are many times thicker than the overburden.

The radiomagnetotelluric (RMT) method has been used to collect data in the Grunfor area in Denmark to estimate the potential of the method under Danish conditions. The Grundfor area was chosen because it has been intensively mapped with several geophysical methods in connection with the Danish Environmental Research Programme. The results of previous measurements thus form a good basis for comparison.

Within the framework of hydrogeological studies for additional water supply for the city of Bulawayo, Zimbabwe, a cooperation between the University of Zimbabwe, Lund Technical University, Sweden, and the University of Aarhus, Denmark, with support from the Swedish International Development Agency has led to a geophysical survey of the large Kalahari and Karoo sedimentary basins in North Matebeleland, for the purpose of assessing water resources.

Resistivity profile data, resulting from combined sounding and profiling, can now be collected with considerable speed due to the development of computerised measuring equipment. Owing to a higher data density and larger quantity of these profile measurements, rapid interpretation procedures are needed. We have developed a fast approximate interpretation procedure based on a deconvolution using the 2D Frechet kernel for the homogeneous halfspace.

The widespread problems with the quality of ground water call on the one hand for a much more detailed and on the other hand a regional covering with geophysical data, when performing a hydrogeophysical investigation.

The use of geophysical methods for hydrogeological investigations has received much attention in the last decade due to the increased demand on water resources for industry and domestic use and due to the threat to the ground water resources from agricultural use and leakage from waste deposits and dump sites. A much more detailed data coverage of larger areas is needed than has hitherto been the case, and the effectiveness of the methods applied and the strategy of the field work is of utmost importante.

A prospective survey of all registered treatment or measures carried out against the wishes of the patients during the first year after enforcement of the new Danish legislation in 1989 in the Psychiatric Hospital in Aalborg is presented. A total of 376 treatment situations and measures were registered. These involved 235 patients. It was found that 79 forced admissions had occurred together with 36 situations where patients who had been admitted voluntarily were forced to remain in hospital. The survey does not demonstrate any major change in the pattern of enforced measures and treatment after introduction of the new legislation. The working conditions for the new advisors for patients prescribed by the new law are described. These were found to be badly paid, idealistic and hard working. The daily administration of the law has been found to be quite bureaucratic. In addition, complains by patients concerning enforced measures and treatment are described. It is found that no verdicts contradict the steps taken by the hospital.

Survival was compared between 135 patients (II) with intracranial tumours (IT) diagnosed with the aid of CT and 170 cases of IT (I) diagnosed in the same department prior to the introduction of CT. Apart from fewer cases of oligodendrogliomata in group II, the distribution into histological types was identical in the two groups. The age and sex distributions were identical. The percentages in the groups (I/II) of operations (85.7/60.7), autopsy (41.1/15.3) and histological determination of the tumour (87.6/58.5) had decreased considerably while employment of chemotherapy had increased (1.8/20.7). On the whole, survival from the time of diagnosis was found to be better in group (II) (p = 0.026). Survival from the onset of the disease was the same (p = 0.47) indicating that CT had resulted in earlier diagnosis but not a generalized improvement in survival in the entire group of tumour patients. Significantly better survival was found for the histologically verified malignant tumours in group II both for the primary tumours (p = 0.001) and for metastases (p = 0.0058). In this group, survival was found to be improved both from the time of diagnosis (p = 0.0001) and from the onset of symptoms (p = 0.015). It appears from the literature that there is a generalized tendency to omit histological verification of IT frequently in cases where CT suggests a hopeless prognosis. Greater advantages as regards survival with CT may probably be obtained with more frequent employment of stereotactic biopsy.

Pearl millet, Pennlsetum americanum (L.) Leeke, is a robust, annual bunchgrass that is grown on more than 35 million acres in the world, mainly in the semiarid tropics. It is particularly well adapted to nutrientpoor, sandy soils and low rainfall, but improved varieties respond to good cultural conditions. It is recognized as one of the most drought resistant cereals and appears to be as heat tolerant as sorghum. Research is being conducted in Kansas to increase pearl millet's potential as a cereal crop in semi-arid, grain producing areas.

Recently a monochromatic multiple data taking mode has been demonstrated for diffraction experiments using a RITA type cold neutron spectrometer with a multi-bladed analyser and a position-sensitive detector. Here, we show how this mode can be used in combination with a flexible radial collimator to perform real inelastic neutron scattering experiments. We present the results from inelastic powder, single crystal dispersion and single crystal constant energy mapping experiments. The advantages and complications of performing these experiments are discussed along with a comparison between the imaging mode and the traditional monochromatic focussing mode.