29 research outputs found
A Systemic Functional Linguistics Approach to the Academic Language in Seventh Grade Social Studies
The research questions addressed in this project are, what genres and Theme progressions are common in the History Alive! text, and what linguistic resources make up Themes? The aim of this capstone was to inform the instruction of English learners when using a secondary level social studies text, by understanding how language is used in this genre. This research presents rationale for a text analysis using the Systemic Functional Linguistics (SFL) approach, then utilizes this method to conduct an analysis guided by the research questions. The author discusses the findings, focusing on implications for learner comprehension and instruction. The author found that an SFL analysis resulted in a deeper level of textual understanding, identifying specific ways that language is used to make meaning in the social studies genre. This understanding can be used to tailor instructional and literacy strategies to address the specific demands and traits of the text
Towards a consolidation of worldwide journal rankings - A classification using random forests and aggregate rating via data envelopment analysis
AbstractThe question of how to assess research outputs published in journals is now a global concern for academics. Numerous journal ratings and rankings exist, some featuring perceptual and peer-review-based journal ranks, some focusing on objective information related to citations, some using a combination of the two. This research consolidates existing journal rankings into an up-to-date and comprehensive list. Existing approaches to determining journal rankings are significantly advanced with the application of a new classification approach, ‘random forests’, and data envelopment analysis. As a result, a fresh look at a publication׳s place in the global research community is offered. While our approach is applicable to all management and business journals, we specifically exemplify the relative position of ‘operations research, management science, production and operations management’ journals within the broader management field, as well as within their own subject domain
The role of postsynaptic AMPA receptors in stabilizing presynaptic inputs
The establishment of functional neuronal circuits relies on the formation of excess synapses, followed by the elimination of inappropriate connections. Although the stabilization of presynaptic inputs is critical for the development of functional circuits, the signals that regulate presynaptic stability are not known. Here we report that synapse formation in cortical cultures is highly dynamic and involves the formation and elimination of synapses at a high rate. During the peak of synaptogenesis, only approximately 50% of putative synapses are stable over an hour. The stability of presynaptic inputs is strongly correlated with the presence of postsynaptic AMPA but not NMDA receptors. Removal of postsynaptic AMPA receptors leads to a decrease in the absolute number of excitatory presynaptic inputs, as well as in the fraction of synaptic contacts that are stabilized. Overexpression of AMPA receptors increases excitatory presynaptic input number and overexpression of AMPA receptors along with neuroligin-1 in 293T cells is sufficient to stabilize presynaptic inputs onto heterologous cells. The ability of AMPA receptors to stabilize presynaptic inputs is not dependent on receptor activity and instead relies on structural interactions mediated by the N-terminal domain of the AMPA receptor subunit GluR2. These observations indicate that an AMPA receptor-associated signal functions as a retrograde signal to regulate presynaptic stabilit
Low Cerebrospinal Fluid Hypocretin Levels Found in Familial Narcolepsy
Objective: This report describes abnormal hypocretin neurotransmission in a case of familial narcolepsy. Background: Narcolepsy is a chronic, often-disabling central nervous system disorder characterized by excessive daytime sleepiness and abnormal rapid eye movement (REM) sleep features including cataplexy, a loss of muscle tone triggered by emotion. The cause of human narcolepsy is unknown. Several familial cases have been described, but most cases are sporadic (95%). An abnormality of hypocretin neurotransmission has been found in a majority of sporadic cases. Methods: Hypocretin-1 levels were measured in the cerebrospinal fluid of the narcoleptic proband of a family with several affected members. Results: The proband was found to have a hypocretin-1 deficiency. Conclusion: Abnormal hypocretin neurotransmission is found in familial, as well as sporadic, narcolepsy. (C) 2001 Elsevier Science B.V. All rights reserved
Regulation of synaptic stability by AMPA receptor reverse signaling
The establishment of neuronal circuits relies on the stabilization of functionally appropriate connections and the elimination of inappropriate ones. Here we report that postsynaptic AMPA receptors play a critical role in regulating the stability of glutamatergic synapses. Removal of surface AMPA receptors leads to a decrease in the number and stability of excitatory presynaptic inputs, whereas overexpression increases synapse number and stability. Furthermore, overexpression of AMPA receptors along with Neuroligin-1 in 293T cells is sufficient to stabilize presynaptic inputs from cortical neurons onto heterologous cells. The stabilization of presynaptic inputs by AMPA receptors is not dependent on receptor-mediated current and instead relies on structural interactions mediated by the N-terminal domain of the glutamate receptor 2 (GluR2) subunit. These observations indicate that transsynaptic signaling mediated by the extracellular domain of GluR2 regulates the stability of presynaptic terminals
Methods for verification of 3D printed anatomic model accuracy using cardiac models as an example
Abstract Background Medical 3D printing has brought the manufacturing world closer to the patient’s bedside than ever before. This requires hospitals and their personnel to update their quality assurance program to more appropriately accommodate the 3D printing fabrication process and the challenges that come along with it. Results In this paper, we explored different methods for verifying the accuracy of a 3D printed anatomical model. Methods included physical measurements, digital photographic measurements, surface scanning, photogrammetry, and computed tomography (CT) scans. The details of each verification method, as well as their benefits and challenges, are discussed. Conclusion There are multiple methods for model verification, each with benefits and drawbacks. The choice of which method to adopt into a quality assurance program is multifactorial and will depend on the type of 3D printed models being created, the training of personnel, and what resources are available within a 3D printed laboratory
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Natural Language Processing Technologies in Radiology Research and Clinical Applications.
The migration of imaging reports to electronic medical record systems holds great potential in terms of advancing radiology research and practice by leveraging the large volume of data continuously being updated, integrated, and shared. However, there are significant challenges as well, largely due to the heterogeneity of how these data are formatted. Indeed, although there is movement toward structured reporting in radiology (ie, hierarchically itemized reporting with use of standardized terminology), the majority of radiology reports remain unstructured and use free-form language. To effectively "mine" these large datasets for hypothesis testing, a robust strategy for extracting the necessary information is needed. Manual extraction of information is a time-consuming and often unmanageable task. "Intelligent" search engines that instead rely on natural language processing (NLP), a computer-based approach to analyzing free-form text or speech, can be used to automate this data mining task. The overall goal of NLP is to translate natural human language into a structured format (ie, a fixed collection of elements), each with a standardized set of choices for its value, that is easily manipulated by computer programs to (among other things) order into subcategories or query for the presence or absence of a finding. The authors review the fundamentals of NLP and describe various techniques that constitute NLP in radiology, along with some key applications
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3D printing based on cardiac CT assists anatomic visualization prior to transcatheter aortic valve replacement
Background3D printing is a promising technique that may have applications in medicine, and there is expanding interest in the use of patient-specific 3D models to guide surgical interventions.ObjectiveTo determine the feasibility of using cardiac CT to print individual models of the aortic root complex for transcatheter aortic valve replacement (TAVR) planning as well as to determine the ability to predict paravalvular aortic regurgitation (PAR).MethodsThis retrospective study included 16 patients (9 with PAR identified on blinded interpretation of post-procedure trans-thoracic echocardiography and 7 age, sex, and valve size-matched controls with no PAR). 3D printed models of the aortic root were created from pre-TAVR cardiac computed tomography data. These models were fitted with printed valves and predictions regarding post-implant PAR were made using a light transmission test.ResultsAortic root 3D models were highly accurate, with excellent agreement between annulus measurements made on 3D models and those made on corresponding 2D data (mean difference of -0.34 mm, 95% limits of agreement: ± 1.3 mm). The 3D printed valve models were within 0.1 mm of their designed dimensions. Examination of the fit of valves within patient-specific aortic root models correctly predicted PAR in 6 of 9 patients (6 true positive, 3 false negative) and absence of PAR in 5 of 7 patients (5 true negative, 2 false positive).ConclusionsPre-TAVR 3D-printing based on cardiac CT provides a unique patient-specific method to assess the physical interplay of the aortic root and implanted valves. With additional optimization, 3D models may complement traditional techniques used for predicting which patients are more likely to develop PAR