131,887 research outputs found
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
On the role of vitamin D in multiple sclerosis
No full textMultiple sclerosis (MS) is among the most common neuroinflammatory diseases across the globe and is autoimmune mediated in nature. This progressive, highly debilitating disease often leaves individuals wheelchair bound within 15-25 years of onset. MS is characterized by inflammatory lesions that appear in unpredictable locations around the central nervous system. Lesions can be visualized using magnetic resonance imaging (MRI) technology. As neuroinflammation continues and lesions accumulate, patients can experience a wide array of progressively worsening symptoms including but not limited to motor impairments, sensory disturbances, loss of control of bodily functions, and/or neuropathic pain, depending on the location of lesion formations. There are different types of MS, the most common being relapsing-remitting MS (RRMS) seen in about 85% of cases and characterized by periods of symptom remission followed by flare-ups. A large majority of these patients go on to develop secondary progressive MS (SPMS) where neurological damage and patient decline is progressive and continuous. Primary progressive MS (PPMS) is seen in about 10% of cases and is characterized by progressive and continuous patient decline from the outset of disease. Other rarer forms of MS do exist but will not be discussed further. Research aimed at MS is at an all-time high and the timing could not be better: its global incidence and prevalence is climbing.
For decades MS has been thought of as a disease caused by dysfunctional CD4+ T-helper 1 (Th1) cells. It is now known that many different cell types contribute to MS pathophysiology. These other cell types include macrophages and dendritic cells of the innate immune system due to their expression of MHC class II molecules that function to activate CD4+ Th1 cells. More recent research has implicated CD8+ T-cells and B-cells in contributing to disease through direct destruction of neural cells that express MHC class I molecules and through the generation of autoantibodies, respectively. While these discoveries are important and provide hope for future breakthrough treatments, there are still enormous gaps in the medical community’s knowledge of what causes MS.
The epidemiologic pattern of MS prevalence has for many decades interested scientists and hinted at a potential cause of this disease. MS tends to affect white individuals with genetic ties to northern Europe, but this relationship may not still hold true, as MS incidence and prevalence may be rising faster in black populations compared to other races/ethnicities, at least in the United States. MS occurs nearly 3 times as often in females than in males, and is strongly associated with Epstein-Barr virus (EBV) infection—especially in those that go on to develop infectious mononucleosis (IM). MS prevalence increases markedly in regions north of 40 degrees North latitude or south of 40 degrees South latitude. MS risk also changes depending on body mass index (BMI) considerations, migration history, and in families with a genetic history of the disease. It is well-accepted that MS has a genetic component, the most important of which is the presence of the HLA-DRB1*1501 allele that codes for certain proteins in MHC class II molecules. However, genetics alone are unable to sufficiently account for MS risk as the concordance rate for identical twins with MS is only 25-30%. These well-established findings imply that some unknown environmental factor(s) must be contributing to MS initiation and progression.
All of the environmental factors listed above have a common connecting thread that is logically and empirically verifiable: vitamin D. This fat-soluble vitamin can either be endogenously synthesized in the skin after exposure to ultraviolet B (UVB) light or consumed through the diet, the former being of more importance to humans.
Epidemiologic patterns suggest a protective role for vitamin D in MS, where low or deficient levels of vitamin D may be a contributor to increased risk for MS. Populations living at greater latitudes, north or south, have significantly greater prevalence of MS which coincides with the reduction of endogenously produced vitamin D in these regions due to a lesser amount of UVB light (and of lower intensity) experienced year-round. Increases in BMI, especially increased adiposity, correlate with increased risk for MS and with prevalence of vitamin D deficiency. Women tend to naturally have greater adiposity than men, thus increasing their risk for MS. Estrogens and vitamin D have been shown to act synergistically to protect against MS, therefore vitamin D deficiency may increase risk for MS in women.
Vitamin D is a known immunomodulatory agent that promotes tolerogenic immune states. Vitamin D also offsets many of the harmful effects caused by EBV, among these including repression of B-cell differentiation into plasma cells, reduced MHC II expression, and promotion of B cell apoptosis. This serves to repress deleterious immunoglobulin secretion by B-cells. Vitamin D is also immunologically beneficial as it promotes regulatory T cell function and their expression of protective cytokines, and through its inhibition of inflammatory Th1 and Th17 cell functions. In total, the immunomodulatory mechanisms of vitamin D are important as the immunological states produced by vitamin D are exactly the opposite of those observed in MS patients and MS animal models. Research in vitamin D is gaining attention as the scientific community is quickly discovering that its true physiologic role extends far beyond its classical function as a calcium regulator. Indeed, rapidly evolving research is revealing roles for vitamin D in cardiovascular function and blood pressure regulation, brain development and neurological function, and even in the prevention of certain cancers. However, this thesis will focus on its most well-known function secondary to calcium regulation: immunomodulation and its anti-inflammatory capabilities.
The last portion of this thesis will present information advocating for the increase in minimum dietary intake of vitamin D from its current value of 800 IU/day to 5,000 IU/day. While a more than 5-fold increase may seem drastic, the tolerable upper limit is at least 10,000 IU/day even by the most conservative of estimates—the true upper limit is probably around 20,000 IU/day and may even be 50,000 IU/day. The global prevalence of vitamin D deficiency is so extensive that some authors have even considered it a global pandemic: upwards of 50% of the entire world population may be deficient in this crucial vitamin. Increasing vitamin D supplementation is an extremely low risk way to reduce risk for MS and other diseases
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Investigating Relationships Between Healthcare Worker Hand Hygiene and Healthcare-Associated Infections in Pediatric Populations: An Interventional Study
No full textHealthcare-associated infections (HAIs) are a public health burden that contribute to significant morbidity, mortality, hospital stays, and healthcare costs. HAIs disproportionately affect certain groups who often require special infection prevention and control (IPC) considerations, such as immunocompromised, neonatal, and pediatric populations. Hand hygiene (HH) is the most effective strategy to reduce HAIs. Yet HH compliance among healthcare workers (HCWs) often does not meet recommended guidelines, necessitating education and interventions to increase adherence. This study assessed the impact of an HH campaign on HCW HH compliance and examined subsequent HAI incidence at a mid-size pediatric acute care hospital in the United States. The campaign used staff education, increased administrative oversight, and real-time HH compliance monitoring from overt and covert hand hygiene observers to determine HH adherence. To address HAI trends, patient data from electronic health records were compiled, analyzed, and used in HAI calculations.
Pre-intervention baseline data was collected over a 3-month period and analyzed in comparison to 3-months of intervention and 2-months of post-intervention data. Upon completion of the post-intervention period, changes in HH compliance were compared to the shifts in incidence of HAIs. The results showed a significant whole-house increase in HH compliance, rising from a 79.8% pre-intervention compliance to a 93.7% compliance at the end of the post-intervention period. Highly trafficked and high-risk areas like the Emergency Department, the Rehabilitation Unit, and the Pediatric Intensive Care Unit increased in HH compliance. Subsequently, there was a decrease in whole-house HAIs, with a pre-intervention average rate of 4.45 and a post-intervention average rate of 3.18. Three out of eight examined HAI subtypes examined had average post-intervention period rates that were less than their pre-intervention rate.
Findings from this HH campaign and HAI data analysis highlight the importance of targeted IPC interventions. The success of the intervention underscores the value of prioritizing HH and HH initiatives for healthcare workers and their patients’ health and safety. Outside of just reducing HAIs, HH provides a cost-effective measure that can reduce the strain on healthcare systems. This intervention reinforces the necessity of HH and IPC measurements to maintain and improve public health
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Scholarly Communication and Publishing Lunch and Learn Talk #11: The ULS Open Access Author Fee Fund
No full textAt the May 2014 talk, you will learn about the ULS Open Access Author Fee Fund--what it is, why we do it, how it works, and how the program is going so far
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