Local surface conductivity of transition metal oxides mapped with true atomic resolution.

The introduction of transition metal oxides for building nanodevices in information technology promises to overcome the scaling limits of conventional semiconductors and to reduce global power consumption significantly. However, oxide surfaces can exhibit heterogeneity on the nanoscale e.g. due to relaxation, rumpling, reconstruction, or chemical variations which demands for direct characterization of electronic transport phenomena down to the atomic level. Here we demonstrate that conductivity mapping is possible with true atomic resolution using the tip of a local conductivity atomic force microscope (LC-AFM) as the mobile nanoelectrode. The application to the prototypical transition metal oxide TiO2 self-doped by oxygen vacancies reveals the existence of highly confined current paths in the first stage of thermal reduction. Assisted by density functional theory (DFT) we propose that the presence of oxygen vacancies in the surface layer of such materials can introduce short range disturbances of the electronic structure with confinement of metallic states on the sub-nanometre scale. After prolonged reduction, the surfaces undergo reconstruction and the conductivity changes from spot-like to homogeneous as a result of surface transformation. The periodic arrangement of the reconstruction is clearly reflected in the conductivity maps as concluded from the simultaneous friction force and LC-AFM measurements. The second prototype metal oxide SrTiO3 also reveals a comparable transformation in surface conductivity from spot-like to homogeneous upon reduction showing the relevance of nanoscale inhomogeneities for the electronic transport properties and the utility of a high-resolution LC-AFM as a convenient tool to detect them.

Impact of Fe doping on the electronic structure of SrTiO3 thin films determined by resonant photoemission.

Epitaxial thin films of Fe doped SrTiO3 have been studied by the use of resonant photoemission. This technique allowed us to identify contributions of the Fe and Ti originating electronic states to the valence band. Two valence states of iron Fe2+ and Fe3+, detected on the base of x-ray absorption studies spectra, appeared to form quite different contributions to the valence band of SrTiO3. The electronic states within the in-gap region can be attributed to Fe and Ti ions. The Fe2+ originating states which can be connected to the presence of oxygen vacancies form a broad band reaching binding energies of about 0.5 eV below the conduction band, while Fe3+ states form in the gap a sharp feature localized just above the top of the valence band. These structures were also confirmed by calculations performed with the use of the FP-LAPW/APW+lo method including Coulomb correlations within the d shell. It has been shown that Fe doping induced Ti originating states in the energy gap which can be related to the hybridization of Ti and Fe 3d orbitals.

[Relationship between time of ossification center appearance and hip joint development stage using Graf's method]. / Zaleznosc czasu pojawiania sie obrazu jadra kostnienia glowy kosci udowej od stopnia rozwoju stawu biodrowego, okreslanego wedlug metody Grafa.

The aim of this paper was to relate time of the ossification center appearance and development stage according to Graf. Retrospective analysis included 4546 sonograms in children from 1 to 6 months of age and 1252 sonograms in 313 healthy newborns. An earlier appearance of the ossification center was found in females (7 weeks against 10 weeks of life in males). Statistically significant relationship was found between the delay in the ossification center appearance time and hip dysplasia. The delay exceeding 6 months is suggestive of serious pathology and complications in later stages of hip development.

Congenital cystic eye with multiple ocular and intracranial anomalies.

We describe a newborn with congenital cystic eye, contralateral persistent hyperplastic primary vitreous, and cerebrocutaneous abnormalities. The cerebrocutaneous abnormalities consisted of agenesis of the corpus callosum, midbrain deformity, malformed sphenoid bone, right upper eyelid coloboma, and a left periocular hamartoma. The results of karyotype analysis of the patient and his parents were normal. The association of congenital cystic eye with contralateral persistent hyperplastic primary vitreous has not been previously reported, to our knowledge. Although no unifying diagnosis exists for the collection of anomalies demonstrated in this patient, the term cranial ectodermopathy broadly classifies most of the defects.

[The hinge prosthesis in treatment of rheumatoid arthritis and osteoarthritis of the knee]. / Endoproteza zawiasowa w leczeniu zmian reumatoidalnych i zwyrodnieniowych stawu kolanowego.

Fifty two knee arthroplasties with hinge prostheses of guepar and rotating-hinge types were performed in treatment of rheumatoid and osteoarthritis over 12 years. With the use of point scale 49 results were rated good or fair, 3 results were poor.

[Elbow arthroplasty in patients with rheumatoid arthritis of the joint]. / Artroplastyka stawu lokciowego u chorych na reumatoidalne zapalenie stawów.

Fifteen elbow arthroplasties were performed in 15 rheumatoid patients between 1976 and 1988. In 2 cases fascial interposition was abandoned. The indications for surgical treatment were presented and the results analysed. Ten were rated good, 4 fair and 1 poor.

[Surgical treatment of metacarpo-phalangeal joints in patients with rheumatoid arthritis]. / Operacyjne leczenie stawów sródreczno-paliczkowych u chorych na reumatoidalne zapalenie stawow.

The results of surgical treatment of 195 metacarpo-phalangeal joints in 132 rheumatoid patients were evaluated. The indications for each of three operative methods were presented with clinical assessment and Larsen, Dahle, Eek scale of radiological changes taken into consideration. The results of 137 synovectomies, 32 joint replacements and 24 arthroplasties in 88% were rated as good and fair. The advantages of early synovectomy as well as joint replacement in advanced arthritis were underlined.

[Outcome of surgical treatment in patients with rheumatoid wrist arthritis]. / Wyniki leczenia operacyjnego chorych na reumatoidalne zapalenie nadgarstka.

The results of tendon synovectomies, synovectomies, arthrodeses and tendons reconstructions in 117 wrists of 83 rheumatoid patients are reported. Eighty nine percent of good and fair results prove correct selection and timing of surgical treatment.

[Determining the optimal time for synovectomy in rheumatoid arthritis of the knee joint]. / Przyczynek do próby okreslenia momentu synowektomii w przebiegu reumatoidalnego zapalenia stawu kolanowego.

In 108 patients with rheumatoid arthritis in whom before 4 years synovectomy of the knee joint was performed the relationship between the clinical state and selected indices of inflammatory process was studied. The clinical state of patients was evaluated using modified Gschwend test. Using the Mahalanobis D2 test no relationships between the erythrocyte sedimentation rate, Waaler-Rose test results, and seromucoid level during pre-surgery period on one side and the actual clinical state of patients were stated. According to the authors opinion the decision concerning the surgical treatment should be based solely on clinical state of patients and not on indices of inflammatory process.

[Early results of rehabilitation after synovectomy in rheumatoid arthritis of the knee joint]. / Wczesne wyniki usprawniania stawu kolanowego po synowektomii u chorych na reumatoidalne zapalenie stawów.

In 1976-1987 synovectomy was performed in 537 knee joints in 459 patients. Rehabilitation should be performed before and after operation. The used rehabilitation, with respect to early and late synovectomy, was evaluated. The obtained results of early rehabilitation are a stimulus for the use of the adopted method of treatment.

[Evaluation of the results of synovectomy of the knee joint performed in the early period of the rheumatoid process]. / Próba oceny wyników synowektomii stawu kolanowego wykonanej u chorych we wczesnym okresie zaawansowania procesu reumatoidalnego.

The authors analyzed the results of 77 early knee synovectomies in 65 patients with rheumatoid arthritis, performed in 1976-1987. Special attention was paid to pain, exudate, range of motion, flexion contracture, instability, ability to walk, and radiological changes in the Larsen's scale. The patient's subjective evaluation and the surgeon's intraoperative evaluation were also taken into account. The results were excellent --32.5 per cent, good 46.8 per cent, fair 6.5 per cent, and poor 14.2 per cent.

[Endoprosthesis of the knee joint]. / Endoprotezoplastyka stawu kolanowego.

Endoprosthetic replacement of the knee joint is an important, often the terminal stage of surgical treatment in patients with rheumatoid arthritis and gonarthritis. Basing on the results of the over-11-year-experience of the ward, treatment methods were analyzed and various knee prostheses were evaluated. In evaluation, the modified Gschwend's scale was used. Nineteen results were good 18 fair, and 7 poor. An especially important role of proper qualification of a patient to surgery, conditions for insertion of endoprosthesis and the choice of a proper type of endoprosthesis has been stressed.