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Background: Advances in surgical leads have been thought to potentially enable improved low-back pain relief using SCS. A recently introduced 32-contact surgical lead, which couples multiple independent current control and anatomically-based neural targeting stimulation algorithms, allows for patient-specific programming optimization. We present a real world study of this surgical lead. Methods: A multi-center, consecutive, observational study of a new 32-contact surgical lead was carried out, using the Precision Spectra SCS System (Boston Scientific) in 100 subjects out to 12 months post-implant. We examined procedural information, programming parameters, and clinical outcomes including pain reduction (NRS), activities of daily living, and change in pain medications. Results: Surgical lead placement distribution was between T7 and L2, with most at top of T9 (26%). A mean reduction of 5.1 points (SD 2.15, p<0.001) from 7.8 (baseline) to 2.6 in overall pain was observed. A subset of subjects reporting low-back pain only exhibited a mean decrease of 6.0 points (SD 2.12, p<0.001) from 8.3 (baseline) to 2.2. Of these, 83.1% of subjects showed ≥50% back pain reduction. Increases in activities of daily living and reduction in pain medication usage were also observed in majority of subjects. Conclusions: Subjects implanted with a 32-contact surgical lead using a neural targeting algorithm demonstrated significant low-back pain reduction.
We explore how the rheology of dense granular flows is affected by the presence of sidewalls. The study is based on discrete element method simulations of plane-shear flows between two rough walls, prescribing both the normal stress and the shear rate. Results confirm previous observations for different systems: large layers near the walls develop where the local viscosity is not constant, but decreases when approaching the walls. The size of these layers can reach several dozen grain diameters, and is found to increase when the flow decelerates, as a power law of the inertial number. Two non-local models are found to adequately explain such features, namely the kinetic elasto-plastic fluidity (KEP) model and the eddy viscosity model (EV). The analysis of the internal kinematics further shows that the vorticity and its associated length scale may be a key component of these non-local behaviours.
Changes in landscape composition and structure may impact the conservation and management of protected areas. Species that depend on specific habitats are at risk of extinction when these habitats are degraded or lost. Designing robust methods to evaluate landscape composition will assist decision- and policy-making in emerging landscapes. This paper describes a rapid assessment methodology aimed at evaluating land-cover quality for birds, plants, butterflies and bees around seven UK Natura 2000 sites. An expert panel assigned quality values to standard Coordination of Information on the Environment (CORINE) land-cover classes for each taxonomic group. Quality was assessed based on historical (1950, 1990), current (2000) and future (2030) land-cover data, the last projected using three alternative scenarios: a growth-applied strategy (GRAS), a business-as-might-be-usual (BAMBU) scenario, and sustainable European development goal (SEDG) scenario. A quantitative quality index weighted the area of each land-cover parcel with a taxa-specific quality measure. Land parcels with high quality for all taxonomic groups were evaluated for temporal changes in area, size and adjacency. For all sites and taxonomic groups, the rate of deterioration of land-cover quality was greater between 1950 and 1990 than current rates or as modelled using the alternative future scenarios (2000–2030). Model predictions indicated land-cover quality stabilized over time under the GRAS scenario, and was close to stable for the BAMBU scenario. The SEDG scenario suggested an ongoing loss of quality, though this was lower than the historical rate of c. 1% loss per decade. None of the future scenarios showed accelerated fragmentation, but rather increases in the area, adjacency and diversity of high quality land parcels in the landscape.
Second-generation antipsychotics (SGAs) are a frequently and effectively used treatment in schizophrenia and psychotic disorders. Other than First-generation antipsychotics (FGAs), which mainly exert their pharmacologic effect in subcortical dopaminergic systems, SGAs additionally affect partly serotonergically innervated structures within prefrontal areas, such as the Anterior Cingulate Cortex (ACC). However, only few controlled, randomized studies have so far investigated direct and indirect effects of SGAs on the ACC.
The present study investigated differential effects of one SGA (quetiapine) and one FGA (flupentixol) on the human action monitoring system.
ACC function in 18 quetiapine-medicated patients and 13 flupentixol-treated patients suffering from schizophrenia was assessed by means of the error-related negativity (ERN), a neurophysiological marker of ACC function, in a pre-post design. Results Between-group comparisons revealed different effects of quetiapine and flupentixol on ACC function despite similar improvement in psychopathology, cognitive performance and quality of life. Whereas SGA treatment was associated with an increase in amplitudes over time, there were prolonged ERN peak latencies in patients treated with the FGA. Moreover, treatment effects depended on baseline PFC function in both groups.
We conclude that both flupentixol and quetiapine improve prefrontal function especially in patients with weak initial ACC function which might be due to their shared affinity for 5HT-receptors in frontal brain regions. However, since this affinity is more pronounced for SGAs, patients treated with quetiapine seemed to profit more evidently concerning PFC function compared to patients of the flupentixol group, who exhibited a compensatory prolongation of processes.
To describe the identification, management, and clinical characteristics of hospitalized patients with influenza-like illness (ILI) during the peak period of activity of the 2009 pandemic strain of influenza A virus subtype H1N1 (2009 H1N1).
Retrospective review of electronic medical records.
Patients and Setting.
Hospitalized patients who presented to the emergency department during the period October 18 through November 14, 2009, at 4 hospitals in Cook County, Illinois, with the capacity to perform real-time reverse-transcriptase polymerase chain reaction testing for influenza.
Vital signs and notes recorded within 1 calendar day after emergency department arrival were reviewed for signs and symptoms consistent with ILI. Cases of ILI were classified as recognized by healthcare providers if an influenza test was performed or if influenza was mentioned as a possible diagnosis in the physician notes. Logistic regression was used to determine the patient attributes and symptoms that were associated with ILI recognition and with influenza infection.
We identified 460 ILI case patients, of whom 412 (90%) had ILI recognized by healthcare providers, 389 (85%) were placed under airborne or droplet isolation precautions, and 243 (53%) were treated with antiviral medication. Of 401 ILI case patients tested for influenza, 91 (23%) had a positive result. Fourteen (3%) ILI case patients and none of the case patients who tested positive for influenza had sore throat in the absence of cough.
Healthcare providers identified a high proportion of hospitalized ILI case patients. Further improvements in disease detection can be made through the use of advanced electronic health records and efficient diagnostic tests. Future studies should evaluate the inclusion of sore throat in the ILI case definition.
In standard diffraction experiments, ensembles of objects are characterized yielding
averaged, statistical properties (meaningful only if the ensemble is monodisperse).
Focused x-ray beams are used here to localize single nanostructures, identifying and
probing individual objects one by one. In a scanning mode, a 2-dimensional image of the
sample is recorded, which allows the reproducible alignment of a specific nanostructure
for analysis. The x-ray scattered signal is analyzed and modelled, to give access to the
shape, strain and composition inside the single object with sub-micron resolution.
Combination of x-ray microdiffraction technique with other micro-probe experiments on the
very same individual object (simultaneous coupling of x-ray diffraction measurements with
atomic force microscopy (AFM)) is also shown; we prove the possibility to interact with
the objects and to address elastic properties for individual nano-structures out of an
To compare the effects of different skin preparation solutions on surgical-site infection rates.
Three skin preparations were compared by means of a sequential implementation Design. Each agent was adopted as the preferred modality for a 6-month period for all general surgery cases. Period 1 used a povidone-iodine scrub-paint combination (Betadine) with an isopropyl alcohol application between these steps, period 2 used 2% Chlorhexidine and 70% isopropyl alcohol (ChloraPrep), and period 3 used iodine povacrylex in isopropyl alcohol (DuraPrep). Surgical-site infections were tracked for 30 days as part of ongoing data collection for the National Surgical Quality Improvement Project initiative. The primary outcome was the overall rate of surgical-site infection by 6-month period performed in an intent-to-treat manner.
Single large academic medical center.
All adult general surgery patients.
The study comprised 3,209 operations. The lowest infection rate was seen in period 3, with iodine povacrylex in isopropyl alcohol as the preferred preparation method (3.9%, compared with 6.4% for period 1 and 7.1% for period 2; P = .002). In subgroup analysis, no difference in outcomes was seen between patients prepared with povidone-iodine scrub-paint and those prepared with iodine povacrylex in isopropyl alcohol, but patients in both these groups had significantly lower surgical-site infection rates, compared with rates for patients prepared with 2% Chlorhexidine and 70% isopropyl alcohol (4.8% vs 8.2%; P = .001).
Skin preparation solution is an important factor in the prevention of surgical-site infections. Iodophor-based compounds may be superior to Chlorhexidine for this purpose in general surgery patients.
In this paper, we report on range use patterns of birds in relation to tropical forest fragmentation. Between 2003 and 2005, three understorey passerine species were radio-tracked in five locations of a fragmented and in two locations of a contiguous forest landscape on the Atlantic Plateau of São Paulo in south-eastern Brazil. Standardized ten-day home ranges of 55 individuals were used to determine influences of landscape pattern, season, species, sex and age. In addition, total observed home ranges of 76 individuals were reported as minimum measures of spatial requirements of the species. Further, seasonal home ranges of recaptured individuals were compared to examine site fidelity. Chiroxiphia caudata, but not Pyriglena leucoptera or Sclerurus scansor, used home ranges more than twice as large in the fragmented versus contiguous forest. Home range sizes of C. caudata differed in relation to sex, age, breeding status and season. Seasonal home ranges greatly overlapped in both C. caudata and in S. scansor. Our results suggest that one response by some forest bird species to habitat fragmentation entails enlarging their home ranges to include several habitat fragments, whereas more habitat-sensitive species remain restricted to larger forest patches.
Ordering of Co nanoparticles (∼11 nm in diameter) into 2-D and 3-D arrays on Si/Si3N4 substrates in external magnetic field and without field is reported. Arrays of particles were studied by TEM, SEM and GISAXS. The GISAXS measurements were performed at the wavelengths 0.155 nm and 0.336 nm and the spectra were simulated using distorted wave Born approximation approach. From results it follows that 2-D ordered monolayers of particles are composed of hexagonal close-packed mosaic blocks. 3-D arrays – rods are formed along magnetic field direction, being parallel or perpendicular to the substrate surface, when the colloid was more concentrated. Distribution of particles in rods was analyzed only by GISAXS and it was described by close packing of hard spheres. Their effective diameter was 14.7 nm.
The Raman modes of ZnO crystallites of the wurtzite structure were investigated via micro-Raman scattering at resonant and out-of-resonant conditions. The E2 mode was the predominant mode in the spectra for out-of-resonant conditions. For the resonant conditions one mode at the spectral range of the LO's of ZnO single crystal was the predominant mode: its frequency was found to be at ∼ 580 cm−1. The A1(LO) and the E1(LO) modes of a reference ZnO single crystal were found to be 568 cm−1 and 586 cm−1 respectively. Two possible mechanisms were considered that may explain the mode frequency of the crystallites: it can be regarded as a confined E1(LO) mode or as a quasi-LO mode. The UV-photoluminescence of the crystallites was found to have the same energy as that of the single crystal ∼ 3.3 eV, indicating the lack of size-confinement of the electronic states in the crystallites, and inter alia that of the phonon states. Our analysis indicated that the observed frequency can be explained in terms of Loudon's model of a quasi-mode behavior which is due to the crystallites tilt.
AlxGa1-xN films were grown on c-plane sapphire by plasma induced molecular beam epitaxy with 0 ≤ x ≤ 1. The composition and purity of the AlxGa1-xN layers was determined by elastic recoil detection analysis with a relative error of 5% for the Al content. Both X-ray diffraction and atomic force microscopy indicate only a slight decrease in epitaxial quality of the AlxGa1-xN films with increasing Al content up to x = 0.65. X-ray diffraction is used to separate the effects of thermally induced biaxial compressive stress and the alloy composition on the shift of interplanar spacings by measuring both lattice constants. The deviation of the c/a ratio from that of fully relaxed films is a quantitative measure of the biaxial compressive stress leading to a distortion of the unit cell. Values up to 0.5 GPa were observed. By the method proposed, the determination of alloy composition can be corrected for this effect. The results obtained by this method are in very good agreement with the elastic recoil detection measurements substantiating the validity of Vegard's law. These results, compared with optical measurements, indicate that the bowing parameter of the optical bandgap is 1.3 eV within the experimental error.
The GaN on LGO system is the near perfect template (due to extremely high etch selectivity) for developing a viable thin film/compliant GaN substrate. Herein, we report on our efforts to grow GaN on LGO, including improvement of the microscopic surface morphology using pre-growthpretreatments. We also report on the first transferred thin film GaN substrate grown on LGO, transferred off of LGO, and mounted on GaAs. With this approach, (InAl)GaN alloys can be grown on thin GaN films, implementing a truly “compliant” substrate for the nitride alloy system. In addition, the flexibility of bonding to low cost Si, metal or standard ceramic IC packages is an attractive alternative to SiC and HVPE GaN substrates for optimizing cost verses thermal conductivity concerns. We have demonstratedhigh quality growth of GaN on LGO. X-Ray rocking curves of 145 arc-seconds are obtained with only a 0.28 μm thick film. We present data on the out of plane crystalline quality of GaN/LGO material. Likewise, we show 2 orders of magnitude improvement in residual doping concentration and factors of 4 improvement in electron mobility as compared to the only previously reported electrical data. We show substantial vendor to vendor and intra-vendor LGO material quality variations. We have also quantified the desorption of Ga and Li from the surface of LGO at typical growth temperatures using in situ desorption mass spectroscopy and XPS.
We outline the recent developments in CCD imager technology aimed at producing the very large format (8192 × 8192 pixels and larger) detector mosaics required for existing 4-m class and new 8 to 10-m class telescopes. The key technology areas include buttable array design and buttable element packaging, and optimization schemes for QE and readout time. As an example, we highlight the University of Hawaii effort to develop an 8192 × 8192 15 μm pixel CCD mosaic.
The high intensity of solar radiation, obtained with the Odeillo (France) solar furnace facilities, is used to vaporize graphite in inert gas atmosphere. The soot obtained contains C60, C70 and other heavier fullerenes. We discuss the possibility of increasing the evaporation rate of graphite and the yield of soot with this technique. From our last experiments, we obtain a first estimate of the soluble fullerene yield Y ( greater than 12%) and we have shown that 13C enriched fullerenes can be easily produced by this process.
C60 molecules, in diffraction terms, is a quite novel object- covered by scattering points large sphere (D≅0.5acub). The peculiarities of the diffraction distribution and its variation near the order-disorder phase transition are defined from the buckybal's molecular form-factor, fmol. The comparison of calculated diffraction distributions and experimental data proved advantage of the C60 “jump rotation” model at middle and high temperatures.
Reflectance (R) and trasmittance (T) of C60 single-crystals have been measured in the 400-5000 cm-1 range, at room temperature, by using micro-Fourier transform IR spectroscopy. The frequencies of the peaks, appearing in both R and T spectra, are compared with the IR active ones calculated for the simple cubic structure with the bond charge model. It appears that all modes which are expected from symmetry arguments to give a dipole activity are actually observed and the corresponding frequencies are in good agreement with the experimental findings.
A survey of solvents with a wide variation of solubility for C60 and a broad variation in dielectric constant was investigated for possible red shifting of the linear absorbance spectra. Initial analysis shows that very small shifts are achieved. Molar extinction spectra were measured for C60 in each solvent in both the standard mode and with an integrating sphere. Comparison of the two methods has shown strong scattering effects. The UV-vis spectra revealed some broadening in the bands and in some cases supression of strong C60 bands. Fluorescence spectra also show broadening of bands and new fluorescence minima in some solvents indicating formation of complexes between the C60 and those solvents that contain nitrogen.
The symmetry conditions which rule the matching of a fulleren molecule's main axis in a translational lattice are considered. The full set of orientational states for the structure of fullerene are obtained. The different levels of correlations between symmetry axes of icosahedral molecule and cubic lattice are considered. This result used for analysis of orientational ordering models, including modulation structure and discrete orientational glass.