498 research outputs found
Attaining tibiofibular union using an inter-tibiofibular autograft. A series of 43Â cases
SummaryIntroductionThis study consisted of a series of 43 patients with lower leg non-union that were treated with an inter-tibiofibular autograft (ITFG).Material and methodsAfter reviewing the surgical technique, the overall theory behind the treatment is described, including stabilization, soft tissue repair, infection control if necessary and then performing a procedure to help achieve bone union.ResultsAfter an average follow-up of 2years, all the patients achieved union, but some required additional procedures. Only one patient had a delayed reactivation of the infection, which was successfully treated.ConclusionA broad set of indications for ITFG are proposed for lower leg non-union cases, in particular non-infected cases.Level of evidenceLevel IV. Retrospective study
Study of a high spatial resolution 10B-based thermal neutron detector for application in neutron reflectometry: the Multi-Blade prototype
Although for large area detectors it is crucial to find an alternative to
detect thermal neutrons because of the 3He shortage, this is not the case for
small area detectors. Neutron scattering science is still growing its
instruments' power and the neutron flux a detector must tolerate is increasing.
For small area detectors the main effort is to expand the detectors'
performances. At Institut Laue-Langevin (ILL) we developed the Multi-Blade
detector which wants to increase the spatial resolution of 3He-based detectors
for high flux applications. We developed a high spatial resolution prototype
suitable for neutron reflectometry instruments. It exploits solid 10B-films
employed in a proportional gas chamber. Two prototypes have been constructed at
ILL and the results obtained on our monochromatic test beam line are presented
here
Modeling and Optimization of Lactic Acid Synthesis by the Alkaline Degradation of Fructose in a Batch Reactor
The present work deals with the determination of the optimal operating conditions of lactic acid synthesis by the alkaline degradation of fructose. It is a complex transformation for which detailed knowledge is not available. It is carried out in a batch
or semi-batch reactor. The ââTendency Modelingââ approach, which consists of the development of an approximate stoichiometric and kinetic model, has been used.
An experimental planning method has been utilized as the database for model development.
The application of the experimental planning methodology allows comparison between the experimental and model response. The model is then used in an optimization procedure to compute the optimal process. The optimal control problem is converted into a nonlinear programming problem solved using the sequencial quadratic programming procedure coupled with the golden search method. The strategy developed allows simultaneously optimizing the different variables, which may be constrained. The validity of the methodology is illustrated by the determination
of the optimal operating conditions of lactic acid production
Strong, Ultra-narrow Peaks of Longitudinal and Hall Resistances in the Regime of Breakdown of the Quantum Hall Effect
With unusually slow and high-resolution sweeps of magnetic field, strong,
ultra-narrow (width down to ) resistance peaks are observed in
the regime of breakdown of the quantum Hall effect. The peaks are dependent on
the directions and even the history of magnetic field sweeps, indicating the
involvement of a very slow physical process. Such a process and the sharp peaks
are, however, not predicted by existing theories. We also find a clear
connection between the resistance peaks and nuclear spin polarization.Comment: 5 pages with 3 figures. To appear in PR
Magneto-optical evidence for a gapped Fermi surface in underdoped YBa2Cu3O6+x
The infrared (900-1100 cm-1) Faraday rotation and circular dichroism are
measured in the normal state of underdoped High Tc superconductors and used to
study the magneto-transport. YBa2Cu3O6+x thin films are investigated in the
temperature range 10-300 K in magnetic fields up to 8 Tesla and as a function
of oxygen concentration. A dramatic increase of the Hall frequency is observed
for underdoped samples which is not consistent with the approach to a Mott
transition but is consistent with a partial gapping of the Fermi surface as
predicted in charge density wave models.Comment: 14 pages, 4 figure
In situ relationships between microbiota and potential pathobiota in Arabidopsis thaliana.
A current challenge in microbial pathogenesis is to identify biological control agents that may prevent and/or limit host invasion by microbial pathogens. In natura, hosts are often infected by multiple pathogens. However, most of the current studies have been performed under laboratory controlled conditions and by taking into account the interaction between a single commensal species and a single pathogenic species. The next step is therefore to explore the relationships between host-microbial communities (microbiota) and microbial members with potential pathogenic behavior (pathobiota) in a realistic ecological context. In the present study, we investigated such relationships within root-associated and leaf-associated bacterial communities of 163 ecologically contrasted Arabidopsis thaliana populations sampled across two seasons in southwest of France. In agreement with the theory of the invasion paradox, we observed a significant humped-back relationship between microbiota and pathobiota α-diversity that was robust between both seasons and plant organs. In most populations, we also observed a strong dynamics of microbiota composition between seasons. Accordingly, the potential pathobiota composition was explained by combinations of season-specific microbiota operational taxonomic units. This result suggests that the potential biomarkers controlling pathogen\u27s invasion are highly dynamic
Optical Conductivity and Hall Coefficient in High-Tc Superconductors: Significant Role of Current Vertex Corrections
We study AC conductivities in high-Tc cuprates, which offer us significant
information to reveal the true electronic ground states. Based on the
fluctuation-exchange (FLEX) approximation, current vertex corrections (CVC's)
are correctly taken into account to satisfy the conservation laws. We find the
significant role of the CVC's on the optical Hall conductivity in the presence
of strong antiferromagnetic (AF) fluctuations. This fact leads to the failure
of the relaxation time approximation (RTA). As a result, experimental highly
unusual behaviors, (i) prominent frequency and temperature dependences of the
optical Hall coefficient, and (ii) simple Drude form of the optical Hall andge
for wide range of frequencies, are satisfactorily reproduced. In conclusion,
both DC and AC transport phenomena in (slightly under-doped) high-Tc cuprates
can be explained comprehensively in terms of nearly AF Fermi liquid, if one
take the CVC's into account.Comment: 5 page
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