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Background: When measuring young Duchenne Muscular Dystrophy (DMD) patients’ health-related quality of life (HRQoL), parent-proxy reports are heavily relied on. Therefore, it is imperative that the relationship between parent-proxy and child self-report HRQoL is understood. This study examined the level of agreement between children and their parent-proxy rating of the child’s HRQoL. Methods: We used FOR-DMD clinical trial baseline data. HRQoL, measured using the PedsQL inventory, was reported by 178 parent and child (ages 4 to 7 years) dyads. Intracorrelation coefficients (ICC) measured absolute agreement while paired t-tests determined differences in the average HRQoL ratings between groups. Results: The level of agreement between child and parent-proxy ratings of HRQoL was poor for the generic PedsQL scale (ICC: 0.29) and its subscales; and, similarly low for the neuromuscular disease module (ICC:0.16). On average, parents rated their child’s HRQoL as poorer than the children rated themselves in all scales except for psychosocial and school functioning. Conclusions: Child and parent-proxy HRQoL ratings are discordant in this study sample, as occurs in other chronic pediatric diseases. This should be taken into account when interpreting clinical and research HRQoL findings in this population. Future studies should examine reasons for parents’ perception of poorer HRQoL than that reported by their children.
The human rights of persons with mental disabilities represents a frontier area for legal protection. The content and means of enforcing their rights have become topics of both scholarly and popular concern. For two decades, the international community has grappled — somewhat fitfully — with the human rights norms that should guide nations in their care and treatment of these vulnerable groups. International concern has focused not only on problems of arbitrary detention and cruel, inhumane or degrading treatment, but on issues of institutionalization, sterilization, and a broad array of education, treatment and welfare services.
In many countries, obsolete legislation and service delivery models have hindered the realization of both negative and affirmative (“positive resource claims”) human rights.
The charge transport and quantum interference effects in low-dimensional mesoscopic carbon networks prepared using self-assembling were investigated. The mechanism of conduction in low-dimensional carbon networks was found to depend on the annealing temperature of the nitrocellulose precursor. The charge transport mechanism for carbon networks obtained at Tann=750 0C was found to be the hopping conductivity in the entire investigated temperature range. The Coulomb gap near the Fermi level in the density of states was observed in the investigated carbon networks. The width of the Coulomb gap was found to be decreased with the annealing temperature of the carbon structures. The crossover from the strong localization to the weak localization regime of the charge transport in the carbon structures, obtained at Tann=950 0C and Tann=1150 0C, was observed in the temperature range T>100 K and T>20 K, respectively.
Nature assembles nano-scale components using molecular recognition. In the case of DNA, hydrogen bonding is the driving force behind the matching of complementary pairs of single-stranded (SS) DNA to hybridize into a double strand of helical DNA. For the case of antibodies/antigens and ligands/receptors, binding takes places by a combination of electrostatic forces, chemical bonding, and shape mediated effects. In this project, the assembly of micron sized and smaller particles using biologically inspired events such as DNA hybridization and interactions of ligands and receptors is being investigated. Following the case of DNA, a single strand sequence can be attached to the device surfaces, which is complementary to a single strand sequence previously attached to a patterned surface. Using the natural hybridization of DNA, the devices are expected to assemble in solution as designed onto the substrate surface. Single strands of DNA can be used to provide charge on the devices so that long-range electrostatic forces may be used to bring the devices close to the assembly site. We have also used a less complex molecule to add negative charges to the particles allowing them to be guided into place using electric fields. Attachment of these molecules to surfaces is a critical step in the assembly process. Various factors affecting the attachment are being investigated and will be reported. These include sample preparation and conditions for attachment. We have used polystyrene beads as test objects and optimized the capture of the beads using DNA and Avidin/Biotin interactions. When successful, this approach can be used to assemble micro and nano-scale electronic circuitry including heterogeneous integration of materials. Y6.5.1
A method of aligning small amounts of colloidal particles between narrowly spaced electrodes using a combination of conventional nanofabrication and self-assembled monolayers has been developed. Transport measurements were performed on several devices
Three fundamentally different methods were used to fabricate nanometric surface features on polymers or fused silica. Phase separation of binary polymer mixes resulted in randomly distributed features whose depth and shape could be tightly controlled over large areas. Colloidal resist patterned large areas randomly and uniformly with very fine spikes. In contrast e-beam and reactive ion etching were used to create a set of regular spaced pillars on an orthogonal pattern. Some of the surfaces were replicated by in situ polymerization, solvent casting, embossing or melt molding onto polystyrene (PS) or ε–poly caprolactone (ε–PCL). Nanometric features down to 60nm were imprinted onto the polymers with high fidelity. Cells were seeded onto the nanometric surfaces and adhesion, morphology and cytoskeleton investigated. Cells respond to regular features of 170/80nm (width/depth) with reduced adhesion and changes in overall morphology and cytoskeleton. Small nanofeatures (13nm, 35nm depth) made by phase separation on the other hand increased adhesion and promoted cytoskeletal differentiation. The responses of the cells are indicative that nanometric surface features are useful modifications on scaffolds for tissue engineering or on medical implants.
Large scale periodic arrays of Co/Pt multilayer dots with perpendicular magnetic anisotropy are fabricated utilizing optical interference lithography with Ar+ ion lasers operating at wavelengths of 457nm and 244nm, respectively. The experimental technique allows us to fabricate dot-arrays with periodicities ranging between 125nm and 1100nm and with corresponding dot diameters between 70nm and 740nm. The dot-arrays are prepared on (100)-silicon substrates covering a total area of up to 20cm2 with a maximum dot density of about 4.1x1010dots/in2 as well as within the surface of (110)-silicon substrates. The global magnetic properties of the dot-arrays are characterized by the magneto-optical Kerr effect. The micromagnetic properties of a single Co/Pt dot are measured with quantitative magnetic force microscopy (QMFM) by using a MFM-tip, the magnetic properties of which have been calibrated within the point probe approximation with nanofabricated current carrying rings. This allows us to measure quantitatively the z-component of both the magnetization and the stray field of a Co/Pt dot on the nanometer scale.
Co/Pt thin film multilayers with strong perpendicular anisotropy and out-of-plane coercivities of 5-11 kOe were magnetically altered in areas of local ion beam interaction. The ion irradiations were performed by ion projection through silicon stencil masks fabricated by silicon on insulator (SOI) membrane technology. The ion projector at the Fraunhofer Institute for Silicon Technology (ISiT) was operated at 73 keV ion energy and with a 8.7- fold demagnification. After exposure to 3 × 1014Ar+/ cm2 magnetic islands smaller than 100 nm in diameter were resolved in the Co/Pt multilayersby means of magnetic force microscopy. The impact of different ion species (He+, Ar+ and Xe+) and ion energies (10 – 200 keV) on the multilayer structure was evaluated using Monte Carlo simulations. The ballistic interface intermixing was used to predict magnetic coercivity changes for various irradiation conditions. The simulations revealed that with 73 keV Ar+ and Xe+ ions the irradiation dose could be reduced by a factor of 100 and 400 respectively in comparison to 73 keV He+which was verified in the experiments. X-ray reflectivity measurements confirmed that the Co/Pt superlattice structure is slightly weakened during the irradiation and that the surface smoothness of the media is preserved. Using the Ion Projection Process Development Tool (PDT) at IMS-Vienna concentric data tracks including head positioning servo informations were patterned onto a 1” IBM microdrive™ glass disk which was coated with Co/Pt multilayers. In a single exposure step several tracks within an exposure field of 17 mm in diameter were structured by 2 × 1015He+/ cm2 at 45 keV using a 4- fold demagnification set-up.
By blending 3-aminopropyl-siloxane oligomers (pAPS) with chitosan (CHI) self-assembled hybrid films have been obtained. The influence of the incorporation of LiClO4 on the morphology of these transparent and flexible hybrid films has been studied. It was found that when this salt is added in amounts slightly over the limit of the maximal homogeneous incorporation a process of anisotropical crystallization begins. For a hybrid with composition CHI/pAPS/LiClO4 = 0.6/1/0.8M, Video-Enhanced Differential Interference Contrast microscopy (VEC-DIC) of the first three layers of the films showed that each layer have oriented patterns with angles of exactly 60 degrees between the planes. These results in combination with FTIR analysis of the products indicate that lithium ions behave as strong structure directing agent. This system can be considered as a biomimetic model for biomineralization processes. An interaction scheme comprising the components of this hybrid system is proposed.
Fullerite nanotubules of 100 nm to 2 μm radius, up to 200 nm wal thickness and 10 μm length were produced inside etched swift heavy ion tracks in a polymer, by letting fullerence precipitate from a concentrated C60 solution within the tracks. After contacting the tubules on both sides with silver paste, their resistivity was measured as a function of temperature. All of the 13 prepared samples show a complex behaviour that can be described by tw Arrhenius curves, the low temperature branch with activation energy Eact = (1.77 ± 0.2) eV stemming from pure C60, and the high temperature branch being tentatively ascribed to C60Agx with x ≍ 12.4 and Eact = (0.68 ± 0.2) eV, as the letter compound has found to be produced at ambient temperature by C60 / Ag thermal intermixture. Such samples with tw branches of negative temperature coefficients of resistance might be useful to construct advanced thermoresistors.
The preparation of monodisperse Fe nanoparticles and self-assembly into hcp and fcc or fcc-like arrays is described. Here dipolar interactions dominate for the interparticle spacings studied (1.4-3.4 nm). Comparison of the low temperature magnetic properties of multilayer arrays with those of dilute suspensions of the same particles show increased coercivity and slower magnetic relaxation in the arrays. Mean field calculations of magnetic interaction fields suggest the type of ordered structures formed.
The control of nanoholes formed by anodic oxidation of aluminum (Al) was investigated using AFM nano-indentation on Al film prior to the anodic oxidation. It is well known that ordered trigonal nanohole arrays are formed under certain voltage conditions of anodic oxidation of Al. We succeeded in forming both tetragonal and trigonal arrays of alumina nanoholes on a SiO2/Si- substrate by using nano-indentation on the surface of sputtered pure Al film. The ordered array of nanoholes was obtained at indentation intervals that were close to the nearest neighbor distance of nanoholes in the self-organization condition. Furthermore, we fabricated tetragonal and hexagonal Al nanodot arrays by the selective removal of porous alumina film.
Optical data over a broad energy range (∼ 0.01 eV to ∼ 6 eV) for a series of La2−xSrxCuO4-δ compounds are obtained in parallel with the Meissner effect and the superconductivity transition temperature, Tc. Two noteworthy trends in the optical spectra are observed as the Sr concentration is increased in small steps from x = 0 to x = 0.3. First is the appearance of a low frequency band in the reflectivity, R, whose strength follows closely the Meissner effect and Tc measured on the same set of samples. The position of the onset of this band is pinned at ∼0.9 eV for all values of x. The origin of this band in R is identified as an absorption process due to an electronic transition with a large oscillator strength. Second is the appearance and disappearance of an intense vibrational mode whose strength also tracks “superconductivity”. This sharp structure in the far infrared is a characteristic vibrational mode associated with the dopant induced electronic state.
Optical reflectance spectra in the range 30–35000 cm-1 and 4–300 K are presented on several YBa2CuxOy phases, as well as different forms of the superconducting YBa2CuxO7−x (polycrystalline pellets, textured pellets with ab-plane oriented surface, and single crystals).
The optical and electrical properties of InAs/GaInSb superlattice mesa photodiodes with a cutoff wavelength around 8 pim are investigated. The influence of the surface potential at the mesa sidewalls on the device properties was studied by fabricating gate-controlled diodes. At least two mechanisms determining the dark current in the reverse bias region can be identified. At high reverse biases bulk bandto- band tunneling dominates while the current at low reverse biases is most likely governed by surface effects. Bulk interband tunneling is further investigated by applying magnetic fields B up to 7 T parallel and perpendicular to the electric field E across the p-n junction.
Photoluminescence spectra of hexagonal GaN were measured in the temperature range T= 2 – 1200 K. We identify the Free Exciton (FX) as the dominant recombination process in our high quality samples for temperatures above 200 K. From the line shape fit of the FX we determine the excitonic band gap shift with temperature. An analysis according to the empirical Varshni equation gives Eg (T)-Eg(0 K) = (-α T2)/(T + β), with α = (7.3 ± 0.3)·10−4 eV/K and β = (594 ± 54) K. We have detected significant differences in the band gap energy at low and higher temperatures for GaN layers grown on different substrate materials. Heating GaN above 1200 K leads to irreversible changes in the near band gap photoluminescence spectra.
We report on the structural characterization of InAs/(GaIn)Sb superlattices (SL) grown by solid-source molecular-beam epitaxy. SL periodicity and overall structural quality were assessed by high-resolution X-ray diffraction and Raman spectroscopy. Spectroscopic ellipsometry was found to be sensitive to the (GaIn)Sb alloy composition.