3,166 research outputs found
Design and fabrication of 3D-printed anatomically shaped lumbar cage for intervertebra disc (IVD) degeneration treatment
Spinal fusion is the gold standard surgical procedure for degenerative spinal conditions when conservative therapies have been unsuccessful in rehabilitation of patients. Novel strategies are required to improve biocompatibility and osseointegration of traditionally used materials for lumbar cages. Furthermore, new design and technologies are needed to bridge the gap due to the shortage of optimal implant sizes to fill the intervertebral disc defect. Within this context, additive manufacturing technology presents an excellent opportunity to fabricate ergonomic shape medical implants. The goal of this study is to design and manufacture a 3D-printed lumbar cage for lumbar interbody fusion. Optimisations of the proposed implant design and its printing parameters were achieved via in silico analysis. The final construct was characterised via scanning electron microscopy, contact angle, x-ray micro computed tomography (μCT), atomic force microscopy, and compressive test. Preliminary in vitro cell culture tests such as morphological assessment and metabolic activities were performed to access biocompatibility of 3D-printed constructs. Results of in silico analysis provided a useful platform to test preliminary cage design and to find an optimal value of filling density for 3D printing process. Surface characterisation confirmed a uniform coating of nHAp with nanoscale topography. Mechanical evaluation showed mechanical properties of final cage design similar to that of trabecular bone. Preliminary cell culture results showed promising results in terms of cell growth and activity confirming biocompatibility of constructs. Thus for the first time, design optimisation based on computational and experimental analysis combined with the 3D-printing technique for intervertebral fusion cage has been reported in a single study. 3D-printing is a promising technique for medical applications and this study paves the way for future development of customised implants in spinal surgical applications
Processing of strong flux trapping high T(subc) oxide superconductors: Center director's discretionary fund
Magnetic suspension effect was first observed in samples of YBa2Cu3O7/AgO(Y-123/AgO) composites. Magnetization measurements of these samples show a much larger hysteresis which corresponds to a large critical current density. In addition to the Y-123AgO composites, recently similar suspension effects in other RE-123/AgO, where RE stands for rare-Earth elements, were also observed. Some samples exhibit even stronger flux pinning than that of the Y-123/AgO sample. An interesting observation was that in order to form the composite which exhibits strong flux trapping effect the sintering temperature depends on the particular RE-123 compound used. The paper presents the detailed processing conditions for the formation of these RE-123/AgO composites, as well as the magnetization and critical field data
Simple Frameshifts in MIS Postoperative Pain Management Significantly Reduce Opiate Prescriptions
Aims for Improvement The intervention aimed to reduce narcotics provided to patients after MIS by reducing number of narcotic prescriptions and amount prescribed by 25% without affecting patientreported pain scores Usage measured in Morphine Equivalent Doses (MED) MED and pain score assessed at 3 time points: post-op day 1 (POD1), discharge (D/C) and follow-up (FU) apt Pre- and Post-intervention cohorts - Month 1 (Pre-intervention): 21 patients and Month 2 (Post-intervention): 30 patient
Electrochemical capacitance of a leaky nano-capacitor
We report a detailed theoretical investigation on electrochemical capacitance
of a nanoscale capacitor where there is a DC coupling between the two
conductors. For this ``leaky'' quantum capacitor, we have derived general
analytic expressions of the linear and second order nonlinear electrochemical
capacitance within a first principles quantum theory in the discrete potential
approximation. Linear and nonlinear capacitance coefficients are also derived
in a self-consistent manner without the latter approximation and the
self-consistent analysis is suitable for numerical calculations. At linear
order, the full quantum formula improves the semiclassical analysis in the
tunneling regime. At nonlinear order which has not been studied before for
leaky capacitors, the nonlinear capacitance and nonlinear nonequilibrium charge
show interesting behavior. Our theory allows the investigation of crossover of
capacitance from a full quantum to classical regimes as the distance between
the two conductors is changed
MMIC power amplifiers as local oscillator drivers for FIRST
The Heterodyne Instrument for the Far-Infrared and Sub- millimeter Telescope requires local oscillators well into the terahertz frequency range. The mechanism to realize the local oscillators will involve synthesizers, active multiplier chains (AMC's) with output frequencies from 71 - 112.5 GHz, power amplifiers to amplify the AMC signals, and chains of Schottky diode multipliers to achieve terahertz frequencies. We will present the latest state-of-the-art results on 70 - 115 GHz Monolithic Millimeter-wave Integrated Circuit power amplifier technology
Radiation-hypersensitive cancer patients do not manifest protein expression abnormalities in components of the nonhomologous end-joining (NHEJ) pathway
Radiation therapy (RT) is utilised for the treatment of around half of all oncology patients during the course of their illness. Despite great clinical progress in the rational deployment of RT, the underlying molecular basis for its efficacy and toxicity are currently imperfectly understood. In this study, we took a biochemical approach to evaluate the potential role of key ionising radiation repair proteins in the treatment outcomes of patients with severe acute or late RT side effects. Lymphoblastoid cell lines were established from blood samples from 36 radiosensitive cases and a number of controls (the latter had had RT but did not develop significant toxicity). The expression level and migration of key proteins from the nonhomologous end-joining (NHEJ) pathway was evaluated by Western blot analysis on cases and controls. We did not observe any abnormalities in expression level or migration pattern of the following NHEJ proteins in radiosensitive cancer cases: Ku70, Ku80, XRCC4, DNA Ligase IV. These important negative results provide evidence that mutations that affect protein expression of these NHEJ components are unlikely to underlie clinical radiation sensitivity
In depth analysis of the Sox4 gene locus that consists of sense and natural antisense transcripts
Available online 17 February 2016SRY (Sex Determining Region Y)-Box 4 or Sox4 is an important regulator of the pan-neuronal gene expression during post-mitotic cell differentiation within the mammalian brain. Sox4 gene locus has been previously characterized with multiple sense and overlapping natural antisense transcripts [1], [2]. Here we provide accompanying data on various analyses performed and described in Ling et al. [2]. The data include a detail description of various features found at Sox4 gene locus, additional experimental data derived from RNA-Fluorescence in situ Hybridization (RNA-FISH), Western blotting, strand-specific reverse-transcription quantitative polymerase chain reaction (RT-qPCR), gain-of-function and in situ hybridization (ISH) experiments. All the additional data provided here support the existence of an endogenous small interfering- or PIWI interacting-like small RNA known as Sox4_sir3, which origin was found within the overlapping region consisting of a sense and a natural antisense transcript known as Sox4ot1.King-Hwa Ling, Peter J. Brautigan, Sarah Moore, Rachel Fraser, Melody Pui-Yee Leong, Jia-Wen Leong, Shahidee Zainal Abidin, Han-Chung Lee, Pike-See Cheah, Joy M. Raison, Milena Babic, Young Kyung Lee, Tasman Daish, Deidre M. Mattiske, Jeffrey R. Mann, David L. Adelson, Paul Q. Thomas, Christopher N. Hahn, Hamish S.Scot
A phase I trial of Capecitabine+Gemcitabine with radical radiation for locally advanced pancreatic cancer
Standard chemoradiotherapy with infusional 5FU for locally advanced pancreatic cancer (LAPC) has limited efficacy in this disease. The combination of Capecitabine (Cap) and Gemcitabine (Gem) are synergistic and are potent radiosensitisers. The aim of this phase I trial was thus to determine the highest administered dose of the Cap plus Gem combination with radical radiotherapy (RT) for LAPC. Patients had LAPC, adequate organ function, ECOG PS 0–1. During RT, Gem was escalated from 20–50 mg m−2 day−1 (twice per week), and Cap 800–2000 mg m−2 day−1 (b.i.d, days 1–5 of each week). Radiotherapy 50.4 Gy/28 fractions/5.5 weeks, using 3D-conformal techniques. Three patients were entered to each dose level (DL). Dose-limiting toxicity(s) (DLTs) were based on treatment-related toxicities. Twenty patients were accrued. Dose level (DL) 1: Cap/Gem; 800/20 mg m−2 day−1 (3 patients), DL2: 1000/20 (12 patients), DL3: 1300/30 (5 patients). Dose-limiting toxicities were observed in DL3; grade 3 dehydration (1 patient) and grade 3 diarrhoea and dehydration (1 patient). Dose level 2 was the recommend phase 2 dose. Disease control rate was 75%: PR=15%, SD=60%. Median overall survival was 11.2 months. The addition of Cap and Gem to radical RT was feasible and active and achieved at relatively low doses
Consistency equations in Randall-Sundrum cosmology: a test for braneworld inflation
In the context of an inflationary Randall-Sundrum Type II braneworld (RS2) we
calculate spectral indices and amplitudes of cosmological scalar and tensor
perturbations, up to second order in slow-roll parameters. Under very simple
assumptions, extrapolating next-order formulae from first-order calculations in
the case of a de Sitter brane, we see that the degeneracy between standard and
braneworld lowest-order consistency equations is broken, thus giving different
signatures of early-universe inflationary expansion. Using the latest results
from WMAP for estimates of cosmological observables, it is shown that future
data and missions can in principle discriminate between standard and braneworld
scenarios.Comment: 13 pages; v3: supersedes the published version, corrected misprint
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