Nucleation of superconductivity in a thin disk with a ring-like defect

We report on the influence of a circular defect on the vortex configuration in a mesoscopic superconducting sample. Effects associated with the pinning force of the circular defect on the configuration and on the vortex entry fields are studied for a very thin disk. We calculate the magnetization loop, vorticity, free energy and superconducting electrons for the disk in presence of an external magnetic field applied perpendicular to the disk plane. The magnetization curves are hysteretic, with paramagnetic response in part of the downward branch, also, in this part we found a vortex-anti-vortex state. © 2013 World Scientific Publishing Company.

High incidence of 'Dag-like' sperm defect in the domestic cat

The occurrence of a high incidence of sperm tail defects in a male domestic cat resembling the known 'Dag-like' defect is reported. Sperm analyses were performed in ejaculated samples collected by an artificial vagina and in testicular and epididymal sperm cells after castration. The following alterations were observed using transmission electron microscope: heavily coiled sperm tails containing several axonemal units enclosed in the same common cell membrane; aberrations in the axonemal main structure; and swollen and unevenly distributed mitochondria in the midpiece. Abnormal modifications in the mitochondrial sheath were also found in sperm cells retrieved from testes and epididymides. Considering these findings, we can conclude that this is the Dag-like defect, described previously in other domestic species and a testicular origin may be involved. © ISFM and AAFP 2012.

Evidence of defect-mediated magnetic coupling on hydrogenated Co-doped ZnO

Hydrogenated bulk Zn1-xCoxO samples were synthesized via standard solid-state reaction route with Co molar concentrations up to 15 at.%. Magnetic characterization demonstrates a room temperature ferromagnetic behavior associated to a paramagnetic Curie-Weiss component. Detailed microstructural analysis was carried out to exclude the presence of extrinsic sources of ferromagnetism. The magnetization increases linearly as a function of Co concentration. Hall measurements reveal an insulating character for the whole set of samples. In this context, the defect mediated magnetic coupling between the Co atoms under the scope of the bound magnetic polarons model is used to interpret the observed room temperature ferromagnetism. © 2012 Elsevier B.V. All rights reserved.

Improvement of an anterior infrabone defect using combined periodontal and orthodontic therapy: a 6-year follow-up case report

Extensive intraosseous lesions represent a clinical challenge for the periodontist. Sites with bone defects have been shown to be at higher risk of periodontitis progression in patients who had not received periodontal therapy. Thus, the aim of this case report was to describe a novel approach for the treatment of 1-walled intraosseous defect by combining nonsurgical periodontal therapy and orthodontic movement toward the bone defect, avoiding regenerative and surgical procedures. A 47-year-old woman underwent the proposed procedures for the treatment of her left central incisor with 9 mm probing depth and 1-walled intraosseous defect in its mesial aspect. Initially, basic periodontal therapy with scaling and root planning was accomplished. Two months later, an orthodontic treatment was planned to eliminate the intraosseous lesion and to improve the interproximal papillary area. Orthodontic root movement toward the osseous defect was performed for 13 months with light forces. After 6 years postoperative it was concluded that combined basic periodontal therapy and orthodontic movement was capable of eliminating the intraosseous defect and improve the esthetics in the interproximal papillary area between the central incisors.

Bacterial cellulose-hydroxyapatite composites with osteogenic growth peptide (OGP) or pentapeptide OGP on bone regeneration in critical-size calvarial defect model

This study aimed to evaluate the potential of bacterial cellulose-hydroxyapatite (BC-HA) composites associated with osteogenic growth peptide (OGP) or pentapeptide OGP(10–14) in bone regeneration in critical-size calvarial defects in mice. In this study, the BC-HA, BC-HA-OGP, and BC-HA-OGP(10–14) membranes were analyzed at 3, 7, 15, 30, 60, and 90 days. In each period, the specimens were evaluated by micro-computed tomography (µCT), descriptive histology, gene expression of bone biomarkers by qPCR and VEGFR-2 (vascular endothelial growth factor) quantification by ELISA. Three days post-operative, Runx2, Tnfrsf11b and Bglap bone biomarkers were upregulated mainly by BC-HA OGP and BC-HA OGP(10–14) membranes, suggesting an acceleration of the osteoblast differentiation/activity with the use of these biomaterials. At 60 and 90 days, a high percentage of bone formation was observed by µCT for BC-HA and BC-HA OGP(10–14) membranes. High expression of some bone biomarkers, such as Alpl, Spp1, and Tnfrsf11b, was also observed for the same membranes on days 60 and 90. In conclusion, the BC-HA membrane promoted a better bone formation in critical-size mice calvarial defects. Nevertheless, incorporation of the peptides at the concentration of 10−9 mol L−1 did not improve bone regeneration potential in the long-term.

New LLLT protocol to speed up the bone healing process-histometric and immunohistochemical analysis in rat calvarial bone defect

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Reconstruction of alveolar bone defect with autogenous bone particles and osseointegrated implants: histologic analysis and 10 years monitoring

Maintaining the volume of the alveolar process after extraction can be achieved by immediate implant placement and guided bone regeneration, with or without the use of biomaterials. The authors present a case report with a 10 years follow-up, rehabilitation using osseointegrated implants in the extraction area and maintenance of the volume of the alveolar process with autogenous cortical bone shavings.

Bone defect repair on the alveolar wall of the maxillary sinus using collagen membranes and temporal fascia: an experimental study in monkeys

Few studies has been done using guided bone regeneration in maxillary sinus defects. AIM: To assess the bone repair process in surgical defects on the alveolar wall of the monkey maxillary sinus, which communicates with the sinus cavity, by using collagen membranes: Gen-derm - Genius Baumer, Pro-tape - Proline and autologous temporal fascia. MATERIALS AND METHODS: In this prospective and experimental study, orosinusal communications were performed in four tufted capuchin monkeys (Cebus apella) and histologic analysis was carried out 180 days after. RESULTS: In the defects without a cover (control), bone proliferation predominated in two animals and fibrous connective tissue predominated in the other two. In defects repaired with a temporal fascia flap, fibrous connective tissue predominated in three animals and bone proliferation predominated in one. In the defects repaired with Gen-derm or Pro-tape collagen membranes there was complete bone proliferation in three animals and fibrous connective tissue in one. CONCLUSIONS: Surgical defect can be repaired with both bone tissue and fibrous connective tissue in all study groups; collagen membranes was more beneficial in the bone repair process than temporal fascia or absence of a barrier.