86 research outputs found
Survival Analysis of Bridge Superstructures in Wisconsin
Although survival analyses have long been used in biomedical research, their application to engineering in general, and bridge engineering in particular, is a more recent phenomenon. In this research, survival (reliability) of bridge superstructures in Wisconsin was investigated using the Hypertabastic accelerated failure time model. The 2012 National Bridge Inventory (NBI) data for the State ofWisconsin were used for the analyses. A recorded NBI superstructure condition rating of 5 was chosen as the end of service life. The type of bridge superstructure, bridge age, maximum span length (MSL) and average daily traffic (ADT) were considered as possible risk factors in the survival of bridge superstructures. Results show that ADT and MSL can substantially affect the survival of bridge superstructures at various ages. The reliability of Wisconsin superstructures at the ages of 50 and 75 years is on the order of 63% and 18%, respectively, when the ADT and MSL values are at Wisconsin’s mean values
Conditional survival analysis for concrete bridge decks
Bridge decks are a significant factor in the deterioration of bridges, and substantially affect long-term bridge maintenance decisions. In this study, conditional survival (reliability) analysis techniques are applied to bridge decks to evaluate the age at the end of service life using the National Bridge Inventory records. As bridge decks age, the probability of survival and the expected service life would change. The additional knowledge gained from the fact that a bridge deck has already survived a specific number of years alters (increases) the original probability of survival at subsequent years based on the conditional probability theory. The conditional expected service life of a bridge deck can be estimated using the original and conditional survival functions. The effects of average daily traffic and deck surface area are considered in the survival calculations. Using Wisconsin data, relationships are provided to calculate the probability of survival of bridge decks as well as expected service life at various ages. The concept of survival dividend is presented and the age when rapid deterioration begins is defined
Analyzing the Effect of Capital Gains and Stock Liquidity on Stock Expected Return
This research investigated the effect of capital gains and stock liquidity on stock expected return. The stock expected return is measured based on capital assets pricing model. Stock liquidity is measured by stock trading turn over and capital gain is measured by the return made through the changes in stock prices. In order to control other factors that may have an effect on stock expected return, some variables like market to book ratio, size, dividend payout ratio, leverage and profitability have been studied. Research hypotheses tested using regression model based on pooled data. Research sample includes 172 companies listed in Tehran Stock Exchange over the period 2010 – 2014. Results showed that there is not any significant relationship between capital gains and stock expected return. But the results found that stock liquidity has a significant and positive effect on stock expected return. In fact, stock expected return is a direct function of changes in stock liquidity
Experiencing Microaggressions:Four stories of racial microaggressions based on examples from staff and students working on dental clinics
This comic is designed to start conversations about microaggression by presenting four stories from staff and students from our community based on their experiences of racist microaggressions. We hope these stories will lead to more conversations about microaggressions generally, and more specifically, racist microaggressions, leading to a greater understanding of how microaggressions can detrimentally impact people. Identifying racial microaggressions allows us to consider our own behaviour and that of others to help create a community that is fair and inclusive.The examples illustrated in these stories have been adapted from real stories provided by staff and students at Dundee Dental Hospital and Research School
Experiencing Microaggressions:Four stories of racial microaggressions based on examples from staff and students working on dental clinics
This comic is designed to start conversations about microaggression by presenting four stories from staff and students from our community based on their experiences of racist microaggressions. We hope these stories will lead to more conversations about microaggressions generally, and more specifically, racist microaggressions, leading to a greater understanding of how microaggressions can detrimentally impact people. Identifying racial microaggressions allows us to consider our own behaviour and that of others to help create a community that is fair and inclusive.The examples illustrated in these stories have been adapted from real stories provided by staff and students at Dundee Dental Hospital and Research School
Semi-quantitative Detection of Pseudouridine Modifications and Type I/II I/Ii Hypermodifications in Human mRNAs Using Direct Long-Read Sequencing
Here, we develop and apply a semi-quantitative method for the high-confidence identification of pseudouridylated sites on mammalian mRNAs via direct long-read nanopore sequencing. A comparative analysis of a modification-free transcriptome reveals that the depth of coverage and specific k-mer sequences are critical parameters for accurate basecalling. By adjusting these parameters for high-confidence U-to-C basecalling errors, we identify many known sites of pseudouridylation and uncover previously unreported uridine-modified sites, many of which fall in k-mers that are known targets of pseudouridine synthases. Identified sites are validated using 1000-mer synthetic RNA controls bearing a single pseudouridine in the center position, demonstrating systematic under-calling using our approach. We identify mRNAs with up to 7 unique modification sites. Our workflow allows direct detection of low-, medium-, and high-occupancy pseudouridine modifications on native RNA molecules from nanopore sequencing data and multiple modifications on the same strand
Functional and structural lesion network mapping in neurological and psychiatric disorders: a systematic review
BackgroundThe traditional approach to studying the neurobiological mechanisms of brain disorders and localizing brain function involves identifying brain abnormalities and comparing them to matched controls. This method has been instrumental in clinical neurology, providing insight into the functional roles of different brain regions. However, it becomes challenging when lesions in diverse regions produce similar symptoms. To address this, researchers have begun mapping brain lesions to functional or structural networks, a process known as lesion network mapping (LNM). This approach seeks to identify common brain circuits associated with lesions in various areas. In this review, we focus on recent studies that have utilized LNM to map neurological and psychiatric symptoms, shedding light on how this method enhances our understanding of brain network functions. MethodsWe conducted a systematic search of four databases: PubMed, Scopus, and Web of Science, using the term "Lesion network mapping." Our focus was on observational studies that applied lesion network mapping in the context of neurological and psychiatric disorders. ResultsFollowing our screening process, we included 52 studies, comprising a total of 6,814 subjects, in our systematic review. These studies, which utilized functional connectivity, revealed several regions and network overlaps across various movement and psychiatric disorders. For instance, the cerebellum was found to be part of a common network for conditions such as essential tremor relief, parkinsonism, Holmes tremor, freezing of gait, cervical dystonia, infantile spasms, and tics. Additionally, the thalamus was identified as part of a common network for essential tremor relief, Holmes tremor, and executive function deficits. The dorsal attention network was significantly associated with fall risk in elderly individuals and parkinsonism. ConclusionLNM has proven to be a powerful tool in localizing a broad range of neuropsychiatric, behavioral, and movement disorders. It holds promise in identifying new treatment targets through symptom mapping. Nonetheless, the validity of these approaches should be confirmed by more comprehensive prospective studies
Stent-assistant versus non-stent-assistant coiling for ruptured and unruptured intracranial aneurysms: A meta-analysis and systematic review
Background: Several different endovascular and non-invasive treatment methods are suggested for the various types of intracranial aneurysms including simple, balloon-assisted, and stent-assisted coiling (SAC). Previous studies investigated the safety and efficacy of SAC versus non-stent-assisted coiling (non-SAC) but the results were controversial. We aim to perform a systematic review and meta-analysis to compare the efficacy and safety of SAC with non-SAC technique in stratifying by the ruptured and unruptured aneurysms. Methods: PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials were searched in April 2022 for studies investigated the efficacy and safety of SAC versus non-SAC. Results: Overall, 26 studies entered into our qualitative and quantitative synthesis. We found that there was overall lower recurrence rate in SAC versus non-SAC significant (RR: 0.43, 95%CI: 0.33, 0.53). Furthermore, the comparisons were significant in unruptured (RR: 0.63, 95%CI: 0.40, 0.86), ruptured (RR: 0.29, 95%CI), and combination aneurysms (RR: 0.42, 95%CI: 0.30, 0.54). Also, we found higher risk of intraprocedural rupture for SAC versus non-SAC in unruptured aneurysms (RR: 1.40, 95%CI: 1.31, 1.50). Investigating hemorrhagic events risk showed that there was significant difference in ruptured (RR: 1.73, 95%CI: 1.12, 2.34) and combination aneurysms (RR: 0.60, 95%CI: 0.37, 0.82). There was no significant difference in immediate occlusion rate, complete occlusion, and risk of ischemic events in our analysis. Conclusion: Overall, our findings demonstrated that SAC may have higher efficacy in term of recurrence rate, but also may have a higher risk of complications in the treatment of intracranial aneurysms. As there are several factors affecting the outcomes and safety of these interventions, further RCTs controlled for multiple factors are required better guide the neurointerventionists choose the best strategy
Characterization of the volatile oil compositions from Hypericum perforatum L. shoot cultures in different basal media
St. John’s wort (Hypericum perforatum L.) is the most important species of the genus Hypericum and produces a wide range of chemical constituents including essential oil. Regarding advantages of in vitro culture techniques in production of desired metabolites, the present study was aimed to investigate volatile constituents of H. perforatum shoots cultured in different basal media. Shoot cultures were established by culturing six nodes of aseptic plants in three liquid media including MS (Murashige and Skoog), B5 (Gamborg B-5) and half-strength B5 containing 30 g L-1 sucrose and 0.5 mg L-1 BA (6-benzyladenine). According to the results, growth and profile of volatile constituents of cultured shoots were affected by the type of medium used and shoots cultured in the B5 medium exhibited the highest growth which was reached to 42.95 g flask-1. On the other hand, 44 components were totally identified by GC-FID and GC-MS analysis of essential oils of cultured shoots. Decane (27.7%), menthol (8.9%), methyl decanoate (4.6%) and β-elemene (4.6%) were the major volatile constituents of the shoots cultured in MS medium, while eudesma4(15),7-dien-1-β-ol (8.1-7.5%), thymol (7-7.2%) and 1,4-trans-1,7-trans-acorenone (5.2-5.5%) were found as the principal components of shoots cultured in B5 and half-strength B5 media
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