Design of a self-aligned, wide temperature range (300 mK-300 K) atomic force microscope/magnetic force microscope with 10 nm magnetic force microscope resolution

We describe the design of a wide temperature range (300 mK-300 K) atomic force microscope/magnetic force microscope with a self-aligned fibre-cantilever mechanism. An alignment chip with alignment groves and a special mechanical design are used to eliminate tedious and time consuming fibre-cantilever alignment procedure for the entire temperature range. A low noise, Michelson fibre interferometer was integrated into the system for measuring deflection of the cantilever. The spectral noise density of the system was measured to be similar to 12 fm/root Hz at 4.2 K at 3 mW incident optical power. Abrikosov vortices in BSCCO(2212) single crystal sample and a high density hard disk sample were imaged at 10 nm resolution to demonstrate the performance of the system. (C) 2014 AIP Publishing LLC

Is decreased bone mineral density associated with development of scoliosis? A bipedal osteopenic rat model

<p>Abstract</p> <p>Background</p> <p>An association between adolescent idiopathic scoliosis and osteopenia has been proposed to exist. It is still not clear whether there is such an association and if so, whether osteopenia is a causative factor or a consequence. Our previous pilot studies have suggested the presence of osteopenia in scoliotic animals. The aim of this study was to investigate the development of scoliosis in an unpinealectomized bipedal osteopenic rat model, implementing osteoporosis as a causative factor.</p> <p>Methods</p> <p>Fifty Sprague-Dawley rats were rendered bipedal at the 3^rdpostnatal week and separated into control (25 rats) and heparin (25 rats receiving 1 IU/gr body weight/day) groups. DEXA scans after 4 weeks of heparin administration showed low bone mass in the heparin group. Anteroposterior and lateral x-rays of the surviving 42 animals (19 in heparin and 23 in control groups) were taken under anesthesia at the 40^thweek to evaluate for spinal deformity. Additional histomorphometric analysis was done on spine specimens to confirm the low bone mass in heparin receiving animals. Results of the DEXA scans, histomorphometric analysis and radiological data were compared between the groups.</p> <p>Results</p> <p>Bone mineral densities of rats in the heparin group were significantly lower than the control group as evidenced by both the DEXA scans and histomorphometric analyses. However, the incidence of scoliosis (82% in heparin and 65% in control; p > 0.05) as well as the curve magnitudes (12.1 ± 3.8 in heparin versus 10.1 ± 4.3 degrees in control; p > 0.05) were not significantly different. Osteopenic rats were significantly less kyphotic compared to control specimens (p = 0.001).</p> <p>Conclusions</p> <p>This study has revealed two important findings. One is that bipedality (in the absence of pinealectomy) by itself may be a cause of scoliosis in this animal model. Further studies on animal models need to consider bipedality as an independent factor. Secondly, relative hypokyphosis in osteopenic animals may have important implications. The absence of sagittal plane analyses in previous studies makes comparison impossible, but nonetheless these findings suggest that osteopenia may be important in the development of 3D deformity in adolescent idiopathic scoliosis.</p

Biomechanics and anterior cruciate ligament reconstruction

For years, bioengineers and orthopaedic surgeons have applied the principles of mechanics to gain valuable information about the complex function of the anterior cruciate ligament (ACL). The results of these investigations have provided scientific data for surgeons to improve methods of ACL reconstruction and postoperative rehabilitation. This review paper will present specific examples of how the field of biomechanics has impacted the evolution of ACL research. The anatomy and biomechanics of the ACL as well as the discovery of new tools in ACL-related biomechanical study are first introduced. Some important factors affecting the surgical outcome of ACL reconstruction, including graft selection, tunnel placement, initial graft tension, graft fixation, graft tunnel motion and healing, are then discussed. The scientific basis for the new surgical procedure, i.e., anatomic double bundle ACL reconstruction, designed to regain rotatory stability of the knee, is presented. To conclude, the future role of biomechanics in gaining valuable in-vivo data that can further advance the understanding of the ACL and ACL graft function in order to improve the patient outcome following ACL reconstruction is suggested

Theoretical determination of maximum biodiesel blend ratios according to kinematic viscosity values

European Biotechnology Conference -- MAY 05-07, 2016 -- LATVIAWOS: 000380240300146

Convex Instrumented Hemiepiphysiodesis With Concave Distraction: A Preliminary Report

The convex growth arrest (CGA) procedure has been well accepted for treatment of congenital scoliosis as it is a simpler procedure with successful results. However, unpredictability of curve behavior, slow and usually inadequate correction, and necessity of anterior surgery for completeness of the epiphysiodesis are its shortcomings. In a preliminary study we asked whether a modification of the CGA procedure using convex instrumented hemiepiphysiodesis with concave distraction would correct the coronal plane Cobb angles and would correct or maintain sagittal plane local and global kyphosis angles. We also identified complications. We retrospectively reviewed five female patients who underwent the modified procedure. Their mean age at the index operation was 40 months (range, 17-55 months). The patients underwent concave distractions every 6 months. The magnitude of the convex instrumented and concave distracted curves and sagittal plane parameters were determined on the preoperative and most recent followup radiographs. Minimum followup was 26 months (mean, 34 months; range, 26-40 months). In the coronal plane, the preoperative magnitude of the convex instrumented congenital curve averaged 48A degrees. It was corrected to 36A degrees (25%) postoperatively and was further improved to 27A degrees (44%) at the latest followup. For the distracted segment, the mean preoperative curve was 35A degrees, corrected to 16A degrees postoperatively and to 8A degrees at the latest followup, for an average correction of 77%. Sagittal plane alignment was minimally affected from the procedure. In four of the five patients we identified partial pullout of screws for the concave distraction; these were revised at the time of planned lengthening. This procedure may obviate the need for multiple osteotomies and long thoracic fusions in young children with long sweeping thoracic deformities involving multiple anomalous vertebrae. Implant-related complications on the concave side may be avoided using paired pedicle screws at the proximal and distal anchor sites. Level IV, therapeutic study. See the guidelines online for a complete description of level of evidence.Wo

Surgical management of post-SCIWORA spinal deformities in children

Background: Patients with spinal cord injury without radiographic abnormality (SCIWORA) are prone to develop spinal deformities. The purpose of this study is to report on the clinical and radiological features of post-SCIWORA spinal deformities. Methods: Four patients with SCIWORA and spinal deformities requiring surgery were analyzed clinically and radiographically. Results: All four SCIWORA patients developed progressive neuromuscular scoliosis. There were 2 males and 2 females. The mean age at spinal cord injury was 3.9 years (range 6 months to 7 years). Spinal deformity was first noticed at a mean of 17 months after their initial injury (range 9 months to 2 years), and surgical intervention was performed at a mean of 6.5 years following their injury (range 4-11 years). The mean preoperative curve was 54° (range 50-62°). The mean postoperative curve was 9.5° (range 5-16°). The level of injury was T5 in two patients, and T10 and L2 in one patient each. All but the lumbar level injury patient had complete paraplegia. One patient with complete injury (T10) and another with incomplete injury (L2) improved neurologically and were able to walk with the aid of orthoses and crutches. Pelvic obliquity improved in all patients following spinal reconstruction surgery, and none of the patients required additional surgery for spinal deformity. The mean postoperative follow-up was 51.75 months (range 24-93 months). Conclusions: Long scoliotic curves extending to the pelvis should be expected in SCIWORA. Early intervention may prevent severe deformities. Modern instrumentation techniques employing pedicle screws provided satisfactory correction, improved hip subluxation, and did not adversely affect the ambulatory ability or functional level of the patients in this series. © 2010 EPOS

Infected concha bullosa mimicking a malignant lesion on F-18-FDG PET/CT

WOS: 000380182300014PubMed: 2683338

Role of Mean Platelet Volume in Diagnosis of Childhood Acute Appendicitis

Introduction. Acute appendicitis is the leading cause of abdominal pain in children requiring emergency surgical intervention. The aim of this study is to investigate the diagnostic value of MPV in early diagnosis of acute appendicitis cases in pediatric age group. Methods. This study was performed retrospectively. Three hundred five patients operated on with the diagnosis of appendicitis and pathologically found to be acute appendicitis were classified as Group 1 and 305 healthy children were classified as control Group 2. Results. One hundred ninety-seven of 305 cases in Group 1 are males (64.6%), in Group 2, 151 of 305 cases are males (49.5%). The mean MPV in Group 1 was 7.9±0.9 (fL), and whereas in Group 2 was 7.7±0.8 (fL). There was no statistically significant difference regarding MPV values (P>0.05). Conclusion. In our study we detected that mean platelet volume has no diagnostic value in pediatric acute appendicitis cases