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101.
Adductor spasmodic dysphonia (ADSD) adversely affects a speaker's ability to effectively communicate. For many individuals suffering with ADSD, botulinum toxin (Botox) is the chosen treatment to remediate the symptoms. Although Botox's effects on symptom remediation have been examined before, patient perception of improvement post-Botox has been examined less frequently. Further, no studies have addressed the symptomatic changes in older adults that occur after Botox treatment. The Voice Handicap Index (VHI) was used as the instrument to assess older patient's (>65 years) perception of how ADSD impacts certain areas of their life pre- and post-Botox injection. The outcome of the VHI was related to a clinical judgment of voice severity. Participants also completed the Social Readjustment Rating Scale (SRRS) to examine overall stress level, and the outcome of the SRRS was correlated to postinjection VHI scores. Results indicated no significant correlation between VHI scores and voice severity or SRRS ratings. The current study suggests further study of voice outcomes with older adults with ADSD is needed.  相似文献   
102.
The usual mean field decoupling procedure applied to the slave-particle representations of the problems with strong local interaction produces a resonant band, but violates the Luttinger sum rule for the physical single-electron propagator. The number of occupied resonant states is small and equal to the deviation from the sum rule, shedding doubt on the overall results. It is therefore argued and illustrated on the example of the Emery model for the high-T c superconductors that, through the consistent application of the mean field procedure to the Hamiltonian and the propagators, the sum rule is restored and the resonant band conserved. In addition to the resonant band, the electron spectrum contains large number of occupied states close to the bare site-energy of the site with strong repulsion. These results are also related here to the other similar decoupling problems, which also lead to the breakdown of the Luttinger sum rule.Received: 2 July 2003, Published online: 9 September 2003PACS: 71.10.Fd Lattice fermion models (Hubbard model, etc.) - 71.27.+a Strongly correlated electron systems; heavy fermions  相似文献   
103.
We prove that some caracterizations of differentiable real valued functions ([1], [2], [4]) are valid also if these functions take values in a reflexive real Banach space.  相似文献   
104.
We have fabricated sandwich SNS (superconductor/normal metal/superconductor) junctions using in-situ grown c-axis oriented YBaCuO/PrBaCuO/YBaCuO trilayers. We observe supercurrents for PrBaCuO thicknesses up to 130 nm at 4.2 K. To confirm or rule out the presence of shorts through the barrier, the junction behaviour has been further characterised. Magnetic-field and PrBaCuO thickness dependences of the critical current, as well as a correct scaling with the junction area of both the critical current and the normal resistance, appear to indicate a reasonable uniformity for the barriers on the scale of the size of the junctions, typically 10 μm. These results suggest that either we are observing real c-axis transport in PrBaCuO or, if the behaviour is defect dominated, that the criteria commonly used to demonstrate good device behaviour should be applied carefully. The temperature dependence of the junction critical current and normal resistance are also reported and compared.  相似文献   
105.
Structure of self-organized multilayer nanoparticles for drug delivery   总被引:1,自引:0,他引:1  
The combined use of cryo-TEM, dynamic light scattering, and small-angle X-ray and neutron scattering techniques allows a detailed structural model of complex pharmaceutical preparations of soybean lecithin/chitosan nanoparticles used as drug vectors to be worked out. Charge-driven self-organization of the lipid(-)/polysaccharide(+) vesicles occurs during rapid injection, under mechanical stirring, of an ethanol solution of soybean lecithin into a chitosan aqueous solution. We conclude that beyond the charge inversion region of the phase diagram, i.e., entering the redissolution region, the initial stages of particle formation are likely to be affected by a re-entrant condensation effect at the nanoscale. This behavior resembles that at the mesoscale which is well-known for polyion/amphiphile systems. Close to the boundary of the charge inversion region, nanoparticle formation occurs under a maximum condensation condition at the nanoscale and the complexation-aggregation process is driven toward a maximum multilamellarity. Interestingly, the formulation that maximizes vesicle multilamellarity corresponds to that displaying the highest drug loading efficiency.  相似文献   
106.
The interaction of keV He(+), He(2+), and O(5+) ions with isolated alpha and beta isomers of the amino acid alanine was studied by means of high resolution coincidence time-of-flight mass spectrometry. We observed a strong isomer dependence of characteristic fragmentation channels which manifests in strongly altered branching ratios. Despite the ultrashort initial perturbation by the incoming ion, evidence for molecular rearrangement leading to the formation of H(3)(+) was found. The measured kinetic energies of ionic alanine fragments can be sufficient to induce secondary damage to DNA in a biological environment.  相似文献   
107.

The obtainment of sugars from lignocellulosic residues represents a sustainable and versatile platform for the production of a number of bio-based products. Cellulases are a family of enzymes which can effectively hydrolyze the biomass polysaccharides at mild conditions. Cellulolytic fungi belonging to the genera Trichoderma and Aspergillus are the most commonly source of commercial cellulases used so far. More recently, Talaromyces cellulolyticus was also scored as a promising cellulases producer. In comparison to the Trichoderma and Aspergillus systems, Talaromyces enzymes have been less investigated. The present research dealt with the conversion of steam-pretreated corn stover by commercial blend of T. cellulolyticus enzymes with respect to the common blends. The paper also investigated the stability of the enzyme preparation and tested the use of additives (namely Tween 80, Tween 20, and BSA) to improve the enzymes performances and the hydrolysis efficiency. The results indicated that, at the same process conditions, T. cellulolyticus cellulases were more effective and yielded 20% more sugars compared to control blends. Furthermore, the cellulase components displayed a synergistic interaction with hemicellulases. The results indicate that cellulases from T. cellulolyticus are less affected by the high dry matter consistency and the use of additives could increase the total activity by around 50% and β-glucosidase capacity by 10–15%.

  相似文献   
108.
Solid-state ECD (ss-ECD) spectra of a model microcrystalline solid, finasteride, dispersed into a KCl pellet were recorded by using the synchrotron radiation source at the Diamond B23 beamline. Scanning a surface of 36 mm2 with a step of 0.5 mm, we measured a set of ECD imaging (ECDi) spectra very different from each other and from the ss-ECD recorded with a bench-top instrument (1 cm2 area). This is due to the anisotropic part of the ECD (ACD), which averages to zero in solution or on a large number of randomly oriented crystallites, but can otherwise be extremely large. Two-way singular value decomposition (SVD) analysis, through experimental and simulated TDDFT spectra, disclosed that the measured and theoretical principal components are in line with each other. This finding demonstrates that the observed isotropic ss-ECD spectrum is governed by the anisotropy of locally oriented crystals. It also introduces a new quality for ss-ECD measurements and opens a new future for probing and mapping chiral materials in the solid state such as active pharmaceutical ingredients (APIs).  相似文献   
109.
Starting from the random phase approximation for the weakly coupled multiband tightly-bounded electron systems, we calculate the dielectric matrix in terms of intraband and interband transitions. The advantages of this representation with respect to the usual planewave decomposition are pointed out. The analysis becomes particularly transparent in the long wavelength limit, after performing the multipole expansion of bare Coulomb matrix elements. For illustration, the collective modes and the macroscopic dielectric function for a general cubic lattice are derived. It is shown that the dielectric instability in conducting narrow band systems proceeds by a common softening of one transverse and one longitudinal mode. Furthermore, the self-polarization corrections which appear in the macroscopic dielectric function for finite band systems, are identified as a combined effect of intra-atomic exchange interactions between electrons sitting in different orbitals and a finite inter-atomic tunneling.  相似文献   
110.
N-Acetyl-(1-ferrocenylethyl)amine (8) was synthesized by N-acylation of (1-ferrocenylethyl)amine (7) in 84% yield. Reaction of N-acetyl-[1-(1′-bromo-ferrocenyl)ethyl]amine (4) (which was prepared by multistep sequence starting from bromoferrocene) with n-BuLi/ClCOOEt gave 77% of N-acetyl-N-ethoxycarbonyl-(1-ferrocenylethyl)amine (6) instead of the expected ethyl 1′-[1-(acetamido)ethyl]ferrocene-1-carboxylate (5). Both structures were undoubtedly confirmed by (HR)MS spectroscopy and single crystal X-ray structure analysis.  相似文献   
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