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Purpose: Adult scoliosis is sometimes associated with back pain and severe curves can progress over time. Despite scoliosis has been estimated to affect up to 68% of the population over 60, there is scant literature about conservative treatment for adult scoliosis. Recently, we tested a new brace designed to alleviate pain for adult patients with chronic pain secondary to scoliosis. The study aims to test the efficacy of a prefabricated brace in reducing pain in adult scoliosis patients. Methods: Twenty adults (age 67.8 ± 10.5, curve 61.9 ± 12.6° Cobb) with chronic low back pain (cLBP) secondary to Idiopathic Scoliosis (IS) were included. Patients were evaluated at baseline immediately before starting with the brace and after 6 months. Outcome measures were GRS, Oswestry Disability Index (ODI), Roland Morris Questionnaire (RM), COMI. The paired t test, ANOVA and Wilcoxon tests were used for statistical analysis Results: At six months, worst pain, leg pain and back pain were significantly improved: from 7.15 to 5.60, from 5.65 to 4.35 and from 6.55 to 5.25 (p < 0.05). Sixty-five percent of patients achieved the minimal clinically important difference of 2 points for worst pain and leg pain, 55% for back pain. RM and COMI improved (p < 0.05), no differences for ODI. Conclusion: The prefabricated brace showed a significant improvement at 6 months of worst, leg and back pain in most patients in a group of adult women with IS and cLBP. The quality of life didn't change in a clinically significant way even if the patients reported satisfaction with the treatment. Trial registration number and date of registration: ClinicalTrials.gov Identifier: NCT02643290, December 31, 2015. [ABSTRACT FROM AUTHOR]

We evaluated the in situ performance of a newly designed visible and near-infrared ( Vis- NIR) penetrometer to predict clay content for 10 fields, 151 profile locations and 485 samples that span four orders of the USDA Soil Taxonomy across the Pacific Northwest region of the USA. The clay mineralogy of the soil families is mixed and heterogeneous. To minimize the effects of soil moisture, in situ Vis- NIR measurements were taken during the summer in a Mediterranean climate when most soil is at or near wilting point. Partial least squares regression (PLSR) and leave-one-core-out cross-validation were used to assess the different soil Vis- NIR measurements: (i) standard error of prediction ( SEP) = 5.7, residual product differential ( RPD) = 1.69 for in situ, (ii) SEP = 5.3, RPD = 1.83 for laboratory measurements of intact cores and (iii) SEP = 4.7, RPD = 2.0 for laboratory measurements of dried, sieved soil. The two primary factors contributing to larger in situ errors of prediction relative to laboratory-based measurements of dried, sieved soil were (i) scanning an intact soil surface at field moisture compared with dried, sieved-homogenized soil and (ii) problems with instrument drift and referencing in the field. For four of the 10 fields with similar loess soil and 24 cores per field, we found that for all soil preparations ( in situ, intact core and dried, sieved) field-specific calibrations ( SEP = 5.1, RPD = 1.29 for in situ; SEP = 3.3, RPD = 2.0 for dried, sieved samples) out-performed both a single calibration for the four fields and a calibration that included all 10 fields in this study. More research is required to understand better the effects of examining intact rather than crushed-sieved soil material, a potentially important factor for in situ spectroscopy. In situ predictions could probably be improved with a more stable and internally referenced field spectrometer, but even with these challenges the results show that penetrometer-derived in situ spectroscopy can be used to map the variation in soil profile clay content semi-quantitatively. Highlights We evaluated a new Vis- NIR penetrometer foreoptic to predict clay content in situ., We compared sources of error from in situ and laboratory Vis- NIR., Sample preparation markedly affected (intact soil or dried, sieved) Vis- NIR model performance., We identified major differences in clay content with penetrometer-based Vis- NIR spectroscopy. [ABSTRACT FROM AUTHOR]

Recent advances in the fabrication of microelectromechanical systems and their evolution into nanoelectromechanical systems have enabled researchers to measure extremely small forces, masses and displacements. In particular, researchers have developed position transducers with resolution approaching the uncertainty limit set by quantum mechanics. The achievement of such resolution has implications not only for the detection of quantum behaviour in mechanical systems, but also for a variety of other precision experiments including the bounding of deviations from newtonian gravity at short distances and the measurement of single spins. Here, we demonstrate the use of a quantum point contact as a sensitive displacement detector capable of sensing the low-temperature thermal motion of a nearby micromechanical cantilever. Advantages of this approach include versatility due to its off-board design, compatibility with nanoscale oscillators and, with further development, the potential to achieve quantum-limited displacement detection. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) is a powerful imaging technique that typically operates on the scale of millimetres to micrometres. Conventional MRI is based on the manipulation of nuclear spins with radio-frequency fields, and the subsequent detection of spins with induction-based techniques. An alternative approach, magnetic resonance force microscopy (MRFM), uses force detection to overcome the sensitivity limitations of conventional MRI. Here, we show that the two-dimensional imaging of nuclear spins can be extended to a spatial resolution better than 100 nm using MRFM. The imaging of 19F nuclei in a patterned CaF2 test object was enabled by a detection sensitivity of roughly 1,200 nuclear spins at a temperature of 600 mK. To achieve this sensitivity, we developed high-moment magnetic tips that produced field gradients up to 1.4 × 106 T m−1, and implemented a measurement protocol based on force-gradient detection of naturally occurring spin fluctuations. The resulting detection volume was less than 650 zeptolitres. This is 60,000 times smaller than the previous smallest volume for nuclear magnetic resonance microscopy, and demonstrates the feasibility of pushing MRI into the nanoscale regime. [ABSTRACT FROM AUTHOR]

Abstract: Spin interactions are studied between conduction band electrons in GaAs heterostructures and local moments, specifically the spins of constituent lattice nuclei and of partially filled electronic shells of impurity atoms. Nuclear spin polarizations are addressed through the contact hyperfine interaction resulting in the development of a method for high-field optically detected nuclear magnetic resonance sensitive to 108 nuclei. This interaction is then used to generate nuclear spin polarization profiles within a single parabolic quantum well; the position of these nanometer-scale sheets of polarized nuclei can be shifted along the growth direction using an externally applied electric field. In order to directly investigate ion spin dynamics, doped GaMnAs quantum wells are fabricated in the regime of very low Mn concentrations. Measurements of coherent electron spin dynamics show an antiferromagnetic exchange between s-like conduction band electrons and electrons localized in the d-shell of the Mn impurities, which varies as a function of well width. [Copyright &y& Elsevier]

Frequency domain multiplexing, using an actively damped micromechanical cantilever, is used to detect multiple force signals simultaneously. The measurement principle is applied to magnetic resonance force microscopy to allow concurrent measurement of nuclear spin signals originating from distinct regions of the sample, or from multiple spin species. [ABSTRACT FROM AUTHOR]

The authors use a 1.0 μm wide patterned Cu wire with an integrated nanomagnetic tip to measure the statistical nuclear polarization of 19F in CaF2 by magnetic resonance force microscopy. With less than 350 μW of dissipated power, the authors achieve rf magnetic fields over 4 mT at 115 MHz for a sample positioned within 100 nm of the “microwire” rf source. A 200 nm diameter FeCo tip integrated onto the wire produces field gradients greater than 105 T/m at the same position. The large rf fields from the broadband microwire enable long rotating-frame spin lifetimes of up to 15 s at 4 K. [ABSTRACT FROM AUTHOR]

A method for high-field optically detected nuclear magnetic resonance (ODNMR) is developed sensitive to 108 nuclei. Nuclear spin transitions are induced using a radio frequency coil and detected through Faraday rotation spectroscopy. Unlike conventional ODNMR, which is limited to low fields and relies on the measurement of time-averaged luminescence polarization, this technique monitors nuclear polarization through time-resolved measurements of electron spin dynamics. Measurements in a (110) GaAs quantum well reveal 69Ga, 71Ga, and 75As resonances and their quadrupolar splittings while resolving changes in nuclear polarization of 0.02%. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the case of an Italian family with Brown-Vialetto-Van Laere syndrome (BVVLS) which was associated by two novel heterogeous mutations of C20orf54 gene.

We demonstrate the fabrication of scanning superconducting quantum interference devices (SQUIDs) on the apex of sharp quartz scanning probes—known as SQUID-on-tip probes—using conventional magnetron sputtering. We produce and characterize SQUID-on-tips made of both Nb and MoGe with effective diameters ranging from 50 to 80 nm, magnetic flux noise down to 300 n Φ 0 / Hz , and operating fields as high as 2.5 T. Compared to the SQUID-on-tip fabrication techniques used until now, including thermal evaporation and collimated sputtering, this simplified method facilitates experimentation with different materials, potentially expanding the functionality and operating conditions of these sensitive nanometer-scale scanning probes. [ABSTRACT FROM AUTHOR]

We developed a process to fabricate nanoscale metallic gate electrodes on scanning probe cantilevers, including on the irregular surface of protruding cantilever tips. The process includes a floating-layer technique to coat the cantilevers in an electron-beam resist. We demonstrate gate definition through a lift-off process and through an etching process. The cantilevers maintain a high force sensitivity after undergoing the patterning process. Our method allows the patterning of nanoscale devices on fragile scanning probes, extending their functionality as sensors. [ABSTRACT FROM AUTHOR]

We use a scanning superconducting quantum interference device (SQUID) to image the magnetic flux produced by a superconducting device designed for quantum computing. The nanometer-scale SQUID-on-tip probe reveals the flow of superconducting current through the circuit as well as the locations of trapped magnetic flux. In particular, maps of current flowing out of a flux-control line in the vicinity of a qubit show how these elements are coupled, providing insight on how to optimize qubit control. [ABSTRACT FROM AUTHOR]

Using dynamic cantilever magnetometry, we study the vortex lattice and its corresponding melting transition in a micrometer-size crystallite of superconducting NbSe2. Measurements of the cantilever resonance frequency as a function of magnetic field and temperature respond to the magnetization of the vortex-lattice. The cantilever dissipation depends on thermally activated vortex creep motion, whose pinning energy barrier is found to be in good agreement with transport measurements on bulk samples. This approach reveals the phase diagram of the crystallite, and is applicable to other micrometer- or nanometer-scale superconducting samples. [ABSTRACT FROM AUTHOR]

Microstructural and in situ mineral chemistry studies on mantle peridotite xenoliths from the Late Neogene alkaline volcanic center of Cabezo Tallante (SE Spain) reveal an exceptional record of a multi-stage history of deformation, recrystallization, melt–rock interaction and melt intrusion tracking the progressive exhumation of this lithospheric mantle sector. Xenoliths include porphyroclastic to equigranular spinel peridotites, impregnated plagioclase peridotites, and composite xenoliths made up of peridotites intruded first by gabbronorite veins and later by amphibole-bearing pyroxenites. The earliest stage involved subsolidus re-equilibration from garnet- to spinel-facies conditions, represented by rounded opx + spinel ± cpx clusters indicative of precursor garnet. The spinel-facies equilibration was followed by development of a porphyroclastic fabric, accentuated in many xenoliths by spinel trails, in response to shear deformation that may be related to the early stages of Neogene extension. Porphyroclastic spinel peridotites subsequently underwent multiple episodes of reactive porous melt percolation documented by crystallization of undeformed olivine replacing pyroxene porphyroclasts, and of undeformed poikilitic orthopyroxene at the expense of both pyroxene porphyroclasts and newly crystallized olivines. The porphyroclastic and melt–rock reaction textures are progressively obliterated by an equigranular structure developed as the result of static, possibly melt-assisted, annealing recrystallization. Clinopyroxenes in equigranular peridotites (i.e. the most equilibrated with the percolating melts) display slight light rare earth element (REE) depletion and almost flat middle to heavy REE spectra (LaN/YbN = 0·37–0·62; SmN/YbN = 0·89–1·23). Computed equilibrium liquids have an enriched tholeiitic affinity, consistent with the sub-alkaline magmatism of the Alboran Domain. Overall, the tectonic and magmatic stages recorded in spinel peridotites from Tallante are remarkably consistent with the evolution documented in the Ronda peridotites of the western Betics. Reactive porous flow and annealing recrystallization were followed by an impregnation event, documented by crystallization of interstitial (plag ± opx ± ol) aggregates in porphyroclastic and equigranular xenoliths; this indicates further exhumation to shallower depths. Diffuse melt percolation was followed by intrusion of melts with distinct chemical affinity. The first event is documented by thin gabbronoritic–noritic veins, showing opx reaction rims against the host peridotite. Comparable gabbronorites were previously ascribed to slab-derived melts. The norite veins are crosscut by centimeter-thick dikelets of amphibole pyroxenite. Geobarometric estimates and the observed crystallization order (ol–cpx–amph–plag) point to 0·7–0·9 GPa for pyroxenite intrusion. Computed melts in equilibrium with clinopyroxene show alkaline affinity, similar to the host Tallante alkali basalts. Textural and geochemical features in the xenoliths thus indicate that the progressive uplift of the Tallante lithospheric mantle was accompanied by interaction with melts of different sources, reflecting the magmatic evolution of the Alboran Domain in response to lithosphere extension and thinning leading to the formation of the Betic–Rif arc. [ABSTRACT FROM PUBLISHER]

We use sensitive dynamic cantilever magnetometry to measure the magnetic hysteresis of individual magnetic Janus particles. These particles consist of hemispherical caps of magnetic material deposited on micrometer-scale silica spheres. The measurements, combined with corresponding micromagnetic simulations, reveal the magnetic configurations present in these individual curved magnets. In remanence, ferromagnetic Janus particles are found to host a global vortex state with vanishing magnetic moment. In contrast, a remanent onion state with significant moment is recovered by imposing an exchange bias to the system via an additional antiferromagnetic layer in the cap. A robust remanent magnetic moment is crucial for most applications of magnetic Janus particles, in which an external magnetic field actuates their motion. [ABSTRACT FROM AUTHOR]

L'émergence des BHRe, au sein de notre établissement a été exponentielle entre 2016 : 9 nouveaux porteurs et 2018 :97 nouveaux cas. Notre CH a essayé de mettre en place des équipes dédiées selon les préconisations du HCSP du 10 juillet 2013 pour prendre en charge les patients découverts porteurs de BHRe. Devant les difficultés pratiques rencontrées, le choix a été fait d'ouvrir un secteur dédié pour les patients porteurs de BHRe dans le service de maladies infectieuses (accompagné d'une augmentation de moyens). Notre établissement de 800 lits de MCO possède toutes les spécialités médicales et chirurgicales, hors chirurgie cardiaque et neurochirurgie. Création en mai 2018 de 10 lits (±2) : 8 chambres seules et 1 chambre double (2 lits étant gardés disponibles pour tout patient porteur se présentant aux urgences la nuit ou le WE et devant être hospitalisé). Ce secteur permet d'accueillir tout patient adulte porteur de BHRe 24 h/24 avec équipe dédiée (hors réa adulte et soins intensifs ; hématologie stérile ; obstétrique proche du terme ; pédiatrie). Les lits libres restent utilisés pour accueillir des patients non porteurs qui deviennent alors par définition « contact ». L'effectif de ce secteur compte : 1 binôme IDE/AS matin, après midi et nuit avec présence médicale 7j/7. Les professionnels ont été formés à certains gestes spécifiques aux spécialités chirurgicales non pratiqués jusqu'alors tels que les soins de canule de trachéotomie, les drains thoraciques, les tractions par leurs pairs dans les services concernés. Ce secteur a été doté de matériels dédiés : brassards, tensiomètres, dispositifs de recueil des excrétas à usage unique, chariot ménage, lavettes neuves pour entretien. Plus-values : économie pour le CH : moins de lits fermés, plus aucune équipe dédiée créée, donc moins de recours à l'intérim et d'heures supplémentaires. Moins de patients contact générés dans l'établissement, moins de prélèvements pour le laboratoire. Moins de risques d'erreur d'hygiène car personnels formés à la spécificité des spécialités. Collaboration renforcée entre EOH/maladies infectieuses. Les autres services ne supportent plus les contraintes liées à l'accueil d'un patient porteur ; hors découverte fortuite. Accueil des patients porteurs 7 j/7, 24 h/24. Difficultés : plus d'entre aide possible dans le service entre secteur Bhre et non-Bhre alors que l'organisation précédente du service (au vue de la charge de travail) était prévue avec aide entre secteur. Médecins référents d'autres spécialités : difficulté pour se déplacer dans le service. Faire comprendre la nouvelle organisation au sein de l'établissement (utilisation des lits tiroirs). Renfort de l'image de contagiosité du service infectieux vis-à-vis des autres services. Augmentation de la DMS liée à la difficulté de mutation des patients porteurs dans les secteurs d'aval (SSR/EHPAD). La création du secteur BHRe a grandement amélioré les contraintes pesant sur l'ensemble de notre CH, et aucune transmission croisée n'a été objectivée dans ce secteur. [ABSTRACT FROM AUTHOR]

Abstract There is growing recognition that coastal water quality is interdependent with agricultural management in coastal catchments. Economic-incentive-based instruments can be used to internalize the negative externalities from coastal water pollution. Bio-physical and socio-economic heterogeneity across farms is expected to be an important factor in explaining differing rates of adoption of management practices. This paper hypothesises that: i) different types of farmers are likely to respond differently to incentive payments that promote the adoption of management practices for Great Barrier Reef water quality improvement, and ii) if policy makers account for heterogeneity, cost-effectiveness of incentive payments will increase. Results show that if government paid farmers 100% of the transition costs of moving from their current practices to improved practices, and given current technologies, water quality improvement for the case-study region would be approximately 56% (measured as a reduction of dissolved organic nitrogen at the end of river). Total costs for the region would be almost AU$ 30 M over the planning horizon of one cropping cycle of 6 years. Results furthermore show that as the policy seeks more ambitious land-use changes, from common practice to improved practice to aspirational practice, the public cost of incentive payments increase at an exponential rate. Larger farms make the shift sooner as they are able to offset fixed investments against increased revenues over greater areas. [ABSTRACT FROM AUTHOR]

We use a scanning nanometer-scale superconducting quantum interference device to map the stray magnetic field produced by individual ferromagnetic nanotubes (FNTs) as a function of applied magnetic field. The images are taken as each FNT is led through magnetic reversal and are compared with micromagnetic simulations, which correspond to specific magnetization configurations. In magnetic fields applied perpendicular to the FNT long axis, their magnetization appears to reverse through vortex states, that is, configurations with vortex end domains or in the case of a sufficiently short FNT with a single global vortex. Geometrical imperfections in the samples and the resulting distortion of idealized magnetization configurations influence the measured stray-field patterns. [ABSTRACT FROM AUTHOR]

We demonstrate nonlinear coupling between two orthogonal flexural modes of single as-grown GaAs nanowires. The resonant frequency of one mode can be shifted over many line widths by mechanically driving the other mode. We present time-domain measurements of the mode coupling and characterize it further by pump-probe experiments. Measurements show that a geometric nonlinearity causes the frequency of one mode to depend directly on the square amplitude of the other mode. Nearly degenerate orthogonal modes in nanowires are particularly interesting given their potential use in vectorial force sensing. [ABSTRACT FROM AUTHOR]

We investigate the magnetization reversal mechanism in an individual permalloy (Py) nanotube (NT) using a hybrid magnetometer consisting of a nanometer-scale SQUID (nanoSQUID) and a cantilever torque sensor. The Py NT is affixed to the tip of a Si cantilever and positioned in order to optimally couple its stray flux into a Nb nanoSQUID. We are thus able to measure both the NT's volume magnetization by dynamic cantilever magnetometry and its stray flux using the nanoSQUID. We observe a training effect and a temperature dependence in the magnetic hysteresis, suggesting an exchange bias. We find a low blocking temperature TB = 18 ± 2 K, indicating the presence of a thin antiferromagnetic native oxide, as confirmed by x-ray absorption spectroscopy on similar samples. Furthermore, we measure changes in the shape of the magnetic hysteresis as a function of temperature and increased training. These observations show that the presence of a thin exchange-coupled native oxide modifies the magnetization reversal process at low temperatures. Complementary information obtained via cantilever and nanoSQUID magnetometry allows us to conclude that, in the absence of exchange coupling, this reversal process is nucleated at the NT's ends and propagates along its length as predicted by theory. [ABSTRACT FROM AUTHOR]

Usingdynamic cantilever magnetometry we measure an enhanced skyrmion latticephase extending from around 29 K down to at least 0.4 K in singleMnSi nanowires (NWs). Although recent experiments on two-dimensionalthin films show that reduced dimensionality stabilizes the skyrmionphase, our results are surprising given that the NW dimensions aremuch larger than the skyrmion lattice constant. Furthermore, the stabilityof the phase depends on the orientation of the NWs with respect tothe applied magnetic field, suggesting that an effective magneticanisotropy, likely due to the large surface-to-volume ratio of thesenanostructures, is responsible for the stabilization. The compatibilityof our technique with nanometer-scale samples paves the way for futurestudies on the effect of confinement and surfaces on magnetic skyrmions. [ABSTRACT FROM AUTHOR]

We report nonlinear behavior in the motion of driven nanowire cantilevers. The nonlinearity can be described by the Duffing equation and is used to demonstrate mechanical mixing of two distinct excitation frequencies. Furthermore, we demonstrate that the nonlinearity can be used to amplify a signal at a frequency close to the mechanical resonance of the nanowire oscillator. Up to 26 dB of amplitude gain is demonstrated in this way. [ABSTRACT FROM AUTHOR]

As the number of spins in an ensemble is reduced, the statistical fluctuations in its polarization eventually exceed the mean thermal polarization. This transition has now been surpassed in a number of recent nuclear magnetic resonance experiments, which achieve nanometer-scale detection volumes. Here, we measure nanometer-scale ensembles of nuclear spins in a KPF6 sample using magnetic resonance force microscopy. In particular, we investigate the transition between regimes dominated by thermal and statistical nuclear polarization. The ratio between the two types of polarization provides a measure of the number of spins in the detected ensemble. [ABSTRACT FROM AUTHOR]

Soon after the first measurements of nuclear magnetic resonance in a condensed-matter system, Bloch predicted the presence of statistical fluctuations proportional to in the polarization of an ensemble of N spins. Such spin noise has recently emerged as a critical ingredient for nanometre-scale magnetic resonance imaging. This prominence is a consequence of present magnetic resonance imaging resolutions having reached less than (100 nm)3, a size scale at which statistical spin fluctuations begin to dominate the polarization dynamics. Here, we demonstrate a technique that creates spin order in nanometre-scale ensembles of nuclear spins by harnessing these fluctuations to produce polarizations both larger and narrower than the thermal distribution. This method may provide a route to enhancing the weak magnetic signals produced by nanometre-scale volumes of nuclear spins or a way of initializing the nuclear hyperfine field of electron-spin qubits in the solid state. [ABSTRACT FROM AUTHOR]

Using an optimally coupled nanometer-scale SQUID, we measure the magnetic flux originating from an individual ferromagnetic Ni nanotube attached to a Si cantilever. At the same time, we detect the nanotube's volume magnetization using torque magnetometry. We observe both the predicted reversible and irreversible reversal processes. A detailed comparison with micromagnetic simulations suggests that vortexlike states are formed in different segments of the individual nanotube. Such stray-field free states are interesting for memory applications and noninvasive sensing. [ABSTRACT FROM AUTHOR]

Nanoscale magnets might form the building blocks of next generation memories. To explore their functionality, magnetic sensing at the nanoscale is key. We present a multifunctional combination of a nanometer-sized superconducting quantum interference device (nanoSQUID) and a Ni nanotube attached to an ultrasoft cantilever as a magnetic tip. By scanning the Nb nanoSQUID with respect to the Ni tube, we map out and analyze their magnetic coupling, demonstrate the imaging of an Abrikosov vortex trapped in the SQUID structure ― which is important in ruling out spurious magnetic signals ― and reveal the high potential of the nanoSQUID as an ultrasensitive displacement detector. Our results open a new avenue for fundamental studies of nanoscale magnetism and superconductivity. [ABSTRACT FROM AUTHOR]

We probe local charge fluctuations in a semiconductor via laser spectroscopy on a nearby self-assembled quantum dot. We demonstrate that the quantum dot is sensitive to changes in the local environment at the single-charge level. By controlling the charge state of localized defects, we are able to infer the distance of the defects from the quantum dot with ±5 nm resolution. The results identify and quantify the main source of charge noise in the commonly used optical field-eifect devices. [ABSTRACT FROM AUTHOR]

We measure the statistical polarization of quadrupolar nuclear spins in a submicrometer (0.6 µm³) particle of GaAs using magnetic resonance force microscopy. The crystalline sample is cut out of a GaAs wafer and attached to a micromechanical cantilever force sensor using a focused ion beam technique. Nuclear magnetic resonance is demonstrated on ensembles containing less than 5 x 108 nuclear spins and occupying a volume of around (300 nm)³ in GaAs with reduced volumes possible in future experiments. We discuss how the further reduction of this detection volume will bring the spin ensembles into a regime where random spin fluctuations, rather than Boltzmann polarization, dominate their dynamics. The detection of statistical polarization in GaAs therefore represents an important first step toward 3D magnetic resonance imaging of III-V structures on the nanometer scale. [ABSTRACT FROM AUTHOR]

Abstract: We previously reported impaired cholesterol biosynthesis in rodent Huntington Disease (HD) models and HD patients’ fibroblasts and post mortem brains. We also found that plasma levels of 24S-hydroxycholesterol (24OHC), the brain specific elimination product of cholesterol considered a marker of brain cholesterol turnover, were significantly reduced in HD patients at any disease stage. In the present study we analysed by mass spectrometry the fasting plasma levels of cholesterol, its biosynthetic precursors lanosterol and lathosterol, of the whole-body elimination products 27-hydroxycholesterol and of brain 24OHC in a cohort of premanifest and HD patients at different disease stages. We found that the cholesterol precursors lanosterol and lathosterol (both index of whole body cholesterol synthesis), the levels of the bile acid precursor 27-hydroxycholesterol, and of the brain specific 24OHC, were all significantly reduced in manifest HD patients, suggesting that whole-body and brain cholesterol homeostasis are both impaired in HD. [Copyright &y& Elsevier]

Bone metabolic disruption that occurs in bone metastatic prostate cancer could lead to disturbances of calcium metabolism. The prognostic role of either hypocalcemia or hypercalcemia was assessed in a consecutive series of hormone-refractory bone metastatic prostate cancer patients. Serum calcium was measured in 192 patients. The presence of hypocalcemia and hypercalcemia was related with baseline biochemical and clinical characteristics and the role of these two calcium disturbances in predicting prognosis and adverse skeletal-related events (SREs) was assessed. As compared to normocalcemic patients, hypocalcemic patients (n=51) had higher tumor load in bone (P=0.005), higher plasma chromogranin A (CgA, P=0.01), serum alkaline phosphatase (P=0.01), urinary N-telopeptide (NTX, P=0.002) and lower hemoglobin values (P=0.01), while hypercalcemic patients (n=16) had higher plasma CgA (P=0.001) and serum lactate dehydrogenase values (P=0.001), higher bone pain (P=0.003) and a lower frequency of pure osteoblastic lesions (P=0.001). Hypercalcemia was significantly associated with poor prognosis: hazard ratio (HR), 1.9 (95% confidence Interval (CI) 1.2–3.3) and higher risk to develop SREs HR, 2.5 (95% CI 1.2–5.2, P=0.01), while hypocalcemia was not associated with poor prognosis. The prognostic role of hypercalcemia was maintained in multivariate analysis after adjusting for validated prognostic parameters: HR, 2.72 (95% CI 1.1–6.8, P=0.03). These data suggest that serum calcium levels should be taken into account in the clinical decision-making process of bone metastatic prostate cancer patients. Patients with asymptomatic hypercalcemia could benefit of a strict follow-up and an immediate bisphosphonate treatment. Further prospective clinical trials are needed to confirm this finding.Prostate Cancer and Prostatic Diseases (2009) 12, 94–99; doi:10.1038/pcan.2008.10; published online 11 March 2008 [ABSTRACT FROM AUTHOR]

Abstract: Objective: The most commonly used staging system for renal cell carcinoma (RCC) is the tumor-node-metastasis (TNM) system. In the most recent TNM edition, lymph node (LN) involvement is defined as pN0, pN1, or pN2, depending on the number of metastatic LNs (none, 1, or >1). This study evaluated the prognostic value of this classification and tried to improve its clinical impact by considering an additional parameter, that is, LN density (ratio between number of positive LNs and total number of LNs retrieved). Methods: All pathologic reports of radical nephrectomies performed for RCC in two urologic centers between November 1983 and December 1999 were reviewed. For each patient, complete clinical and pathologic data, number of LNs removed, location and number of positive LNs, and LN density were recorded. The Kaplan-Meyer method and the log-rank test were used to calculate cause-specific survival rates and to compare survival curves, respectively. Results: A total of 735 patients underwent radical nephrectomy. Lymphadenectomy was performed in 618 cases, and the rate of positive LNs was 14.2%. The 5-yr cause-specific survival rate of pN+ patients was 18%, with no statistically significant difference between pN1 and pN2. The average number of LNs removed was 13 (range, 1–35). The median number of LNs involved was 3 (range, 1–18). LN density ranged between 3.7% and 100% (median, 22.9%). The number of LNs removed had no impact on survival in pN+ patients. The only significant unfavorable prognostic factors were >4 LNs involved (p =0.02) and LN density >60% (p =0.01). Conclusion: The results show that in RCC the current TNM stratification of positive LNs is not significantly correlated with prognosis. From our data it appears that classification as ≤4 or >4 LNs involved, supported by LN density, better reflects the impact of the disease on survival. [Copyright &y& Elsevier]

The prognostic role of the invasion of the urinary collecting system (UCS) by renal cell carcinoma (RCC) has not attracted a notable amount of attention. The aim of this study was to investigate incidence and prognostic value of UCS involvement in RCC.All pathological reports of radical nephrectomies performed in two centres of urology from November 1983 to December 1999 were reviewed in order to evaluate the invasion of the UCS (calices, renal pelvis, ureter). Patients were divided into two groups according to presence (Group 1) or absence (Group 2) of UCS invasion. The stage was determined according to the TNM 6th edition. Overall and cause-specific survival rates were evaluated. Univariate and multivariate analyses were performed.The evaluable specimens were 671 from the 735 examined; in 64 cases it was not possible to ascertain or to exclude UCS involvement. Invasion of the UCS was found in 59 cases (8.8%). Median follow-up was 59.0 months (range 0–216). Tumours invading the UCS were usually symptomatic, with high nuclear grade and predominantly high stage. At univariate analysis the 5 year overall and cause-specific survival rates of tumours invading the UCS were significantly lower when compared to those without UCS invasion (42.8% versus 60.8% and 45.5% versus 64.7%, respectively). When groups were stratified, according to the pT category, the 5-year cause-specific survival rate was only significantly different for the pT2 category (33.3% versus 76.9%). At the multivariate analysis TNM staging, symptoms at diagnosis and tumour grade were the only independent prognostic factors.The invasion of the UCS by RCC is unusual, particularly in small tumours. UCS involvement does not represent an independent prognostic factor. However, in organ-confined tumours (i.e. pT2) UCS involvement has an influence on the prognosis and should be taken into account when planning adjuvant treatments and follow-up. [Copyright &y& Elsevier]

OBJECTIVE To determine the number of lymph nodes that need to be examined to accurately stage the pN variable in patients undergoing radical nephrectomy (RN) for renal cell carcinoma (RCC). PATIENTS AND METHODS We reviewed the operative and pathology reports of 725 patients with RCC submitted for RN. All tumours were classified using the fifth edition of the Tumour-Nodes-Metastasis classification. For each patient the number of lymph nodes removed was recorded. The patients were divided into five different groups according to the number of nodes removed, i.e. group 1, 1–4; group 2, 5–8; group 3, 9–12; group 4, 13–16; and group 5, ≥ 17. We evaluated the factors that affected the number of lymph nodes removed with nodal dissection and the variables that influenced the incidence of nodal involvement. RESULTS Lymphadenectomy was performed in 608 patients (83.8%); in these patients the rate of lymph node metastases was 13.6%. The median (range) number of nodes removed was 9 (1–43); there was a statistically significant correlation between the number of nodes removed and the percentage of nodal involvement (r = 0.6; P < 0.01). The rate of pN+ was significantly higher in the patients with ≥ 13 than in those with < 13 nodes examined (20.8% vs 10.2%; P < 0.001). For organ-confined and locally advanced tumours there was a statistically significant difference in the pN+ rate between patients with < 13 or ≥ 13 nodes examined (3.4% vs 10.5%, and 19.7% vs. 32.2%, respectively). CONCLUSIONS The proportion of tumours classified as pN+ increased with the number of lymph nodes examined. In RCC,> 12 lymph nodes need to be assessed for optimal staging. [ABSTRACT FROM AUTHOR]