2,666 research outputs found
Reformulating the rj-McMC Algorithm for 3D Inversion of Passive Seismic Data for Near-Surface Characterization
No full textGeophysical subsurface characterization techniques could, due to their non-invasive nature, play a crucial role in the design and subsequent construction of infrastructure in urban & industrial environ- ments. Geo-data specialist company Fugro sees potential in upgrading their current ambient-seismic- noise-tomography workflow, to make use of state-of-the-art inversion schemes with the main goal of increasing the quality and accuracy of the initial-site characterization delivered to clients. In this thesis I explore the feasibility of utilizing the reverse-jump Markov chain Monte Carlo (rj-McMC) algorithm for the inversion of ambient seismic noise for characterization in urban & industrial environments. Specif- ically, testing the potential of scaling down this inversion algorithm to fit in a small scale, near-surface framework. To achieve this, I first carried out analyses to evaluate the appropriate Rayleigh wave frequency range, after which realistic noise hyperparameters, suited for this reduced scale problem, were obtained. Because of the potential exploitation of in-situ borehole measurements, I reformulated the Bayesian prior within the rj-McMC algorithm to implement these constraining shear wave velocity values appropriately. I conducted extensive synthetic experiments to gain insight into the behavior of this adapted algorithm, from which it was concluded that the inherent dynamic discretization partially prevents these constraints from being implemented to their full extent. Nevertheless, promising results lead me to conclude that the use of the rj-McMC algorithm for application in near-surface urban & industrial environments is feasible.Applied Geophysics | IDEA Leagu
Endocannabinoids in amygdala and nucleus accumbens mediate social play reward in adolescent rats
No full textClowns, Fools, and Killers: An Exploration of Horror, Comedy, and Madness Through the Roles of Murderer 2 and Sir Richard Ratcliffe in William Shakespeare\u27s Richard III
No full textThis document is a thesis submitted in partial fulfillment of the Master of Fine Arts degree in Theatre Arts with a Concentration in Musical Theatre. It is a detailed account of author RJ Magee’s artistic and scholarly process in creating the roles of Murderer 2 and Sir Richard Ratcliffe in William Shakespeare’s Richard III. The production was performed as part of Minnesota State University, Mankato’s mainstage season in October of 2022. In five chapters, this thesis chronicles the actor’s process: a preproduction analysis, a historical and critical perspective, a rehearsal and performance journal, a post-production analysis, and a process development analysis. Appendices and works cited are included
RGMs: Structural Insights, Molecular Regulation, and Downstream Signaling
No full textAlthough originally discovered as neuronal growth cone-collapsing factors, repulsive guidance molecules (RGMs) are now known as key players in many fundamental processes, such as cell migration, differentiation, iron homeostasis, and apoptosis, during the development and homeostasis of many tissues and organs, including the nervous, skeletal, and immune systems. Furthermore, three RGMs (RGMa, RGMb/DRAGON, and RGMc/hemojuvelin) have been linked to the pathogenesis of various disorders ranging from multiple sclerosis (MS) to cancer and juvenile hemochromatosis (JHH). While the molecular details of these (patho)biological effects and signaling modes have long remained unknown, recent studies unveil several exciting and novel aspects of RGM processing, ligand–receptor interactions, and downstream signaling. In this review, we highlight recent advances in the mechanisms-of-action and function of RGM proteins
Radiation-induced root surface caries restored with glass-ionomer cement placed in conventional and ART cavity preparations: Results at two years
No full textThe document attached has been archived with permission from the Australian Dental Association (8th Jan 2008). An external link to the publisher’s copy is included.Background: There are no published studies comparing the clinical performances of more-viscous glass-ionomer cement (GIC) restorations when placed using conventional and atraumatic restorative treatment (ART) cavity preparation methods to restore root surface caries. Methods: One dentist used encapsulated Fuji IX GP and Ketac-Molar to restore 72 conventional and 74 ART cavity preparations for 15 patients who had received cervicofacial radiation therapy. Two assessors evaluated the restorations at six, 12, and 24 months for retention, marginal defects and surface wear, and recurrent caries. Results: After two years, the cumulative restoration successes were 65.2 per cent for the conventional and 66.2 per cent for the ART cavity preparations, without statistical or clinical significance (P>0.50). Restoration dislodgement accounted for 82.8 per cent and marginal defects for 17.2 per cent of all failures. There were no instances of unsatisfactory restoration wear or recurrent caries observed. Teeth with three or more restored cervical surfaces accounted for 79.3 per cent of all failures (P<0.0001). Conclusions: For root surface caries restored with GIC, the use of hand instruments only with the ART method was an equally effective alternative to conventional rotary instrumentation for cavity preparation. Larger restorations had higher failures, usually from dislodgement.JY Hu, XC Chen, YQ Li, RJ Smales and KH Yi
Paediatric use of melatonin (Author reply to D. J. Kennaway).
No full textComment on
Paediatric use of melatonin. [Eur J Paediatr Neurol. 2015]
Current role of melatonin in pediatric neurology: clinical recommendations. [Eur J Paediatr Neurol. 2015
Platelet-rich plasma and macular hole surgery: A clue to their mode of action and the influence of anti-platelet agents
No full text\ua9 The Author(s) 2022. Purpose: To present a case of refractory full-thickness macular hole (FTMH), in which autologous platelet-rich plasma (aPRP) was used on two consecutive occasions, and associated with successful closure only after complete cessation of anti-platelet therapy. Methods: Interventional case report. Results: A 63-year-old male with Alport syndrome underwent pars plana vitrectomy with internal limiting membrane peeling and gas for a large FTMH. The patient was on systemic anti-platelet agents for coronary disease. Post-operatively, the FTMH remained open and repeated surgery, augmented with aPRP, was performed. Although a thick pre-retinal coagulum was evident on optical coherence tomography on day one post-surgery, the second surgery failed. Ultimately, successful aPRP-augmented surgical closure of the FTMH was achieved only after complete cessation of systemic anti-platelet agents. Conclusion: Appropriate management of anti-platelet therapy may be relevant when planning aPRP use, though further large-scale studies are needed to assess the precise effect of anti-platelet therapy on the efficacy of aPRP, and to confirm the potential role of aPRP in patients with Alport syndrome
Needle deflection in thermal ablation procedures of liver tumors: a CT image analysis
No full textIntroduction: Accurate needle placement is crucial in image-guided needle interventions. A targeting error may be introduced due to undesired needle deflection upon insertion through tissue, caused by e.g. patient breathing, tissue heterogeneity, or asymmetric needle tip geometries. This paper aims to quantify needle deflection in thermal ablation procedures of liver tumors by means of a CT image analysis. Methods: Needle selection was done by using all clinical CT data that were made during thermal ablation procedures of the liver, ranging from 2008-2016, in the Erasmus MC, the Netherlands. The 3D needle shape was reconstructed for all selected insertions using manual segmentation. Subsequently, a straight line was computed between the entry point of the needle into the body and the needle tip. The maximal perpendicular distance between this straight line and the actual needle was used to calculate needle deflection. Results: In total, 365 needles were included in the analysis ranging from 14G to 17G in diameter. Average needle insertion depth was 95mm (range: 32 mm – 182 mm). Needle deflection was on average 1.3 mm (range: 0.0 mm – 6.5 mm). 54% of the needles (n=196) had a needle deflection of more than one millimeter, whereas 7% of the needles (n=25) showed a large needle deflection of more than three millimeters. Conclusions: Needle deflection in interventional radiology occurs in more than half of the needle insertions. Therefore, deflection should be taken into account when performing procedures and when defining design requirements for novel needles. Further, needle insertion models need to be developed that account for needle deflection.Medical Instruments & Bio-Inspired Technolog
MicroRNAs in epilepsy: pathophysiology and clinical utility
No full textBACKGROUND: Temporal lobe epilepsy is a common and frequently intractable seizure disorder. Its pathogenesis is thought to involve large-scale alterations to the expression of genes controlling neurotransmitter signalling, ion channels, synaptic structure, neuronal death, gliosis, and inflammation. Identification of mechanisms coordinating gene networks in patients with temporal lobe epilepsy will help to identify novel therapeutic targets and biomarkers. MicroRNAs (miRNAs) are a family of small non-coding RNAs that control the expression levels of multiple proteins by decreasing mRNA stability and translation, and could therefore be key regulatory mechanisms and therapeutic targets in epilepsy. RECENT DEVELOPMENTS: In the past 5 years, studies have found changes in miRNA levels in the hippocampus of patients with temporal lobe epilepsy and in neural tissues from animal models of epilepsy. Early functional studies showed that silencing of brain-specific miR-134 using antisense oligonucleotides (antagomirs) had potent antiseizure effects in animal models, whereas genetic deletion of miR-128 produced fatal epilepsy in mice. Levels of certain miRNAs were also found to be altered in the blood of rodents after seizures. In the past 18 months, functional studies have identified nine novel miRNAs that appear to influence seizures or hippocampal pathology. Their targets include transcription factors, neurotransmitter signalling components, and modulators of neuroinflammation. New approaches to manipulate miRNAs have been tested, including injection of mimics (agomirs) to enhance brain levels of miRNAs. Altered miRNA expression has also been reported in other types of refractory epilepsy and our understanding of how miRNA levels are controlled has grown, with studies on DNA methylation indicating epigenetic regulation. Biofluids (blood) of patients with epilepsy have shown differences in quantity of circulating miRNAs, implying diagnostic biomarker potential. WHERE NEXT?: Recent functional studies need to be replicated to build a robust evidence base. The specific cell types in which miRNAs execute their functions and their primary targets have to be identified, to fully explain the phenotypic effects of modulating miRNAs. Delivery of large molecules such as antisense inhibitors or mimics to the brain poses a challenge, and the multi-targeting effects of miRNAs create additional risks of unanticipated side effects. Potential genetic variation in miRNAs should be explored as the basis for disease susceptibility. The latest findings provide a rich source of new miRNA targets, but substantial challenges remain before their role in the pathogenesis, diagnosis, and treatment of epilepsy can be translated into clinical practice
Pharmacological interventions for patients experiencing acute post-operative pain
No full textWhat is pain? It is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. What are goals for postoperative pain management?To increase a patients quality of life, to facilitate a full and healthy recovery, to decrease the risk for complications (Impaired mobility -
pneumonia, pressure ulcers, DVT), to allow for early discharge from the hospital. Conclusion: by using a combination of pharmacological interventions we can more accurately provide pain management to patients by addressing multiple types of pain at once. By performing a thorough pain assessment and using our clinical judgement to determine what pharmacological interventions are necessary, we can move closer to achieving our postoperative pain management goals.Not peer reviewedStudent Research Day Poster (2017
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