6,552 research outputs found
A direct D-bar reconstruction algorithm for recovering a complex conductivity in 2-D
A direct reconstruction algorithm for complex conductivities in
, where is a bounded, simply connected Lipschitz
domain in , is presented. The framework is based on the
uniqueness proof by Francini [Inverse Problems 20 2000], but equations relating
the Dirichlet-to-Neumann to the scattering transform and the exponentially
growing solutions are not present in that work, and are derived here. The
algorithm constitutes the first D-bar method for the reconstruction of
conductivities and permittivities in two dimensions. Reconstructions of
numerically simulated chest phantoms with discontinuities at the organ
boundaries are included.Comment: This is an author-created, un-copyedited version of an article
accepted for publication in [insert name of journal]. IOP Publishing Ltd is
not responsible for any errors or omissions in this version of the manuscript
or any version derived from it. The Version of Record is available online at
10.1088/0266-5611/28/9/09500
Collaboration between local nephrologists and the transplant centre ensures good outcomes in post-transplant care
BACKGROUND
Despite substantial improvements in short-term kidney allograft survival, median long-term survival remains at a standstill. It is unclear whether and to what extent a transplant centre's post-transplant care influences long-term outcomes.
METHODS
We retrospectively analysed 501 single kidney transplant recipients (KTRs) who underwent transplantation between 2009 and 2018 and did not develop rejection or de novo donor-specific antibodies (dnDSA) within the first post-transplant year. After that, KTRs were either followed exclusively every 3 months by the transplant centre (n = 197) or every 3 months by local nephrologists (n = 304) with only yearly follow-up by the transplant centre. We analysed kidney allograft outcomes regarding estimated glomerular filtration rate (eGFR) decline, proteinuria, development of dnDSA and rejection.
RESULTS
No differences between the two groups were observed in the baseline characteristics and the characteristics at the end of the first post-transplant year (PÂ >Â .05). KTRs followed by local nephrologists were comparable to KTRs followed by the transplant centre concerning patient survival (PÂ =Â .541), kidney allograft survival (PÂ =Â .385), eGFR decline (PÂ =Â .488), progression of proteinuria (PÂ >Â .05), the development of dnDSA (PÂ =Â .335) and T-cell-mediated rejection (PÂ =Â .480). KTRs followed by the transplant centre were more likely to undergo indication biopsies in case of allograft dysfunction and dnDSA (PÂ <Â .001). Antibody-mediated rejection was diagnosed earlier and more frequently (PÂ =Â .059), recurrent glomerulonephritis was diagnosed earlier and more frequently (PÂ =Â .026) and immunosuppression was modified earlier and more frequently in response to histological findings (PÂ =Â .038).
CONCLUSIONS
Our findings suggest that close collaboration between local nephrologists and the transplant centre ensures good allograft outcomes independent of the caregiver. Greater biopsy activity in the transplant centre allows for earlier diagnosis of allograft dysfunction as the basis for novel treatment options
Molecular characterisation of congenital myasthenic syndromes in Southern Brazil
Objective To perform genetic testing of patients with congenital myasthenic syndromes (CMS) from the Southern Brazilian state of Parana. Patients and methods Twenty-five CMS patients from 18 independent families were included in the study. Known CMS genes were sequenced and restriction digest for the mutation RAPSN p.N88K was performed in all patients. Results We identified recessive mutations of CHRNE in ten families, mutations in DOK7 in three families and mutations in COLQ, CHRNA1 and CHRNB1 in one family each. The mutation CHRNE c. 70insG was found in six families. We have repeatedly identified this mutation in patients from Spain and Portugal and haplotype studies indicate that CHRNE c. 70insG derives from a common ancestor. Conclusions Recessive mutations in CHRNE are the major cause of CMS in Southern Brazil with a common mutation introduced by Hispanic settlers. The second most common cause is mutations in DOK7. The minimum prevalence of CMS in Parana is 0.18/100 000
Molecular characterisation of congenital myasthenic syndromes in Southern Brazil
Objective To perform genetic testing of patients with congenital myasthenic syndromes (CMS) from the Southern Brazilian state of Parana. Patients and methods Twenty-five CMS patients from 18 independent families were included in the study. Known CMS genes were sequenced and restriction digest for the mutation RAPSN p.N88K was performed in all patients. Results We identified recessive mutations of CHRNE in ten families, mutations in DOK7 in three families and mutations in COLQ, CHRNA1 and CHRNB1 in one family each. The mutation CHRNE c. 70insG was found in six families. We have repeatedly identified this mutation in patients from Spain and Portugal and haplotype studies indicate that CHRNE c. 70insG derives from a common ancestor. Conclusions Recessive mutations in CHRNE are the major cause of CMS in Southern Brazil with a common mutation introduced by Hispanic settlers. The second most common cause is mutations in DOK7. The minimum prevalence of CMS in Parana is 0.18/100 000
Quantum equivalence in Poisson-Lie T-duality
We prove that, general \s-models related by Poisson-Lie T-duality are
quantum equivalent under one-loop renormalization group flow. We reveal general
properties of the flows, we study the associated generalized coset models and
provide explicit examples.Comment: 16 page
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Removing biofilms from microstructured titanium Ex Vivo: A novel approach using atmospheric plasma technology
The removal of biofilms from microstructured titanium used for dental implants is a still unresolved challenge. This experimental study investigated disinfection and removal of in situ formed biofilms from microstructured titanium using cold atmospheric plasma in combination with air/water spray. Titanium discs (roughness (Ra): 1.96 Όm) were exposed to human oral cavities for 24 and 72 hours (n = 149 each) to produce biofilms. Biofilm thickness was determined using confocal laser scanning microscopy (n = 5 each). Plasma treatment of biofilms was carried out ex vivo using a microwave-driven pulsed plasma source working at temperatures from 39 to 43°C. Following plasma treatment, one group was air/water spray treated before re-treatment by second plasma pulses. Vital microorganisms on the titanium surfaces were identified by contact culture (Rodac agar plates). Biofilm presence and bacterial viability were quantified by fluorescence microscopy. Morphology of titanium surfaces and attached biofilms was visualized by scanning electron microscopy (SEM). Total protein amounts of biofilms were colorimetrically quantified. Untreated and air/water treated biofilms served as controls. Cold plasma treatment of native biofilms with a mean thickness of 19 Όm (24 h) to 91 Όm (72 h) covering the microstructure of the titanium surface caused inactivation of biofilm bacteria and significant reduction of protein amounts. Total removal of biofilms, however, required additional application of air/water spray, and a second series of plasma treatment. Importantly, the microstructure of the titanium discs was not altered by plasma treatment. The combination of atmospheric plasma and non-abrasive air/water spray is applicable for complete elimination of oral biofilms from microstructured titanium used for dental implants and may enable new routes for the therapy of periimplant disease
Vegetation and peat characteristics of restiad bogs on Chatham Island (Rekohu), New Zealand
Restiad bogs dominated by Sporadanthus traversii on Chatham Island, New Zealand, were sampled to correlate vegetation patterns and peat properties, and to compare with restiad systems dominated by Sporadanthus ferrugineus and Empodisma minus in the Waikato region, North Island, New Zealand. Classification and ordination resulted in five groups that reflected a disturbance gradient. The largest S. traversii group, which comprised plots from central, relatively intact bogs, had the lowest levels of total nitrogen (mean 1.20 mg cm-3), total phosphorus (mean 0.057 mg cm-3), total potassium (mean 0.083 mg cm-3), and available phosphorus (mean 18.6 ÎŒg cm-3). Modification by drainage, stock, and fires resulted in a decline of S. traversii and an increase of Gleichenia dicarpa fern cover, together with elevated peat nutrient levels and higher bulk density. Compared with peat dominated by Sporadanthus ferrugineus or Empodisma minus in relatively unmodified Waikato restiad bogs, Chatham Island peat under S. traversii has significantly higher total potassium, total nitrogen, available phosphorus, bulk density, and von Post decomposition indices, and significantly lower pH. Sporadanthus traversii and Empodisma minus have similar ecological roles in restiad bog development, occupying a relatively wide nutrient range, and regenerating readily from seed after fire. Despite differences in root morphology, S. traversii and E. minus are the major peat formers in raised restiad bogs on Chatham Island and in Waikato, respectively, and could be regarded as ecological equivalents
Scaling of hadronic transverse momenta in a hydrodynamic treatment of relativistic heavy ion collisions
The transverse momenta of hadrons in central nucleus-nucleus collisions are
evaluated in a boost invariant hydrodynamics with transverse expansion. Quark
gluon plasma is assumed to be formed in the initial state which expands and
cools via a first order phase transition to a rich hadronic matter and
ultimately undergoes a freeze-out. The average transverse momentum of pions,
kaons, and protons is estimated for a wide range of multiplicity densities and
transverse sizes of the system. For a given system it is found to scale with
the square-root of the particle rapidity density per unit transverse area, and
consistent with the corresponding values seen in experiments at
1800 GeV, suggesting a universal behaviour. The average transverse momentum
shows only an approximate scaling with multiplicity density per nucleon which
is at variance with the data.Comment: 6 pages including 9 figure
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