890 research outputs found
Surface Modification of Melt Extruded Poly(ε-caprolactone) Nanofibers: Toward a New Scalable Biomaterial Scaffold.
A photochemical modification of melt-extruded polymeric nanofibers is described. A bioorthogonal functional group is used to decorate fibers made exclusively from commodity polymers, covalently attach fluorophores and peptides, and direct cell growth. Our process begins by using a layered coextrusion method, where poly(ε-caprolactone) (PCL) nanofibers are incorporated within a macroscopic poly(ethylene oxide) (PEO) tape through a series of die multipliers within the extrusion line. The PEO layer is then removed with a water wash to yield rectangular PCL nanofibers with controlled cross-sectional dimensions. The fibers can be subsequently modified using photochemistry to yield a "clickable" handle for performing the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction on their surface. We have attached fluorophores, which exhibit dense surface coverage when using ligand-accelerated CuAAC reaction conditions. In addition, an RGD peptide motif was coupled to the surface of the fibers. Subsequent cell-based studies have shown that the RGD peptide is biologically accessible at the surface, leading to increased cellular adhesion and spreading versus PCL control surfaces. This functionalized coextruded fiber has the advantages of modularity and scalability, opening a potentially new avenue for biomaterials fabrication
Usability Study of Basic File Management on a Shared Storage System: Usability Test on the Lifetime Library Web Interface
The purpose of this study is to understand usability of the web interface of the Lifetime Library, a shared storage system provided by the School of Information and Library Science at the University of North Carolina at Chapel Hill. Eight participants were recruited and were asked to perform a number of file management tasks, such as uploading a file, renaming a file, creating a folder, adding a tag, adding metadata, organizing a folder, and deleting a file, by using the Lifetime Library web interface. Task completion rate, task completion time, perceived difficulty, confidence in completion of task, number of clicks, and comments were collected to understand each task's usability. Partcipants' responses were measured using the System Usability Scale, and written comments were gathered to understand overall usability of the system. From the results, it was found that bulk uploading was the most difficult task for all participants. It was also found that the longer a task takes time to complete, the higher the tendency to perceive the task as difficult. The results of the study suggested areas for improvement in the usability of the current system, such as placement of menu items, consistency between the main menu and the side bar menu, clear right-click menu, and visibility of notification messages.Master of Science in Information Scienc
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Purification and characterization of microbial protease produced extracellularly from Bacillus subtilis FBL-1
An ammonium sulfate precipitation of
fermentation broth produced by Bacillus subtilis FBL-1
resulted in 2.9-fold increase of specific protease activity.
An eluted protein fraction from the column chromatographies
using DEAE-Cellulose and Sephadex G-75 had 94.2- and
94.9-fold higher specific protease activity, respectively.
An SDS-PAGE revealed a band of purified protease at
approximately 37.6 kDa. Although purified protease showed
the highest activity at 45°C and pH 9.0, the activity remained stable in temperature range from 30 to 50°C and pH range from 7.0 to 9.0. Protease activity was activated by metal ions such as Ca2+, Mg2+, Mn2+, Fe2+, Ca2+ and K+, but
10 mM Fe3+ significantly inhibited enzyme activity (53%).
Protease activity was inhibited by 2 mM EDTA as a
metalloprotease inhibitor, but it showed good stability
against surfactants and organic solvents. The preferred
substrates for protease activity were found to be casein
(100%) and soybean flour (71.6%)
Predictive performance of ultrasonography-based radiomics for axillary lymph node metastasis in the preoperative evaluation of breast cancer
Purpose: The purpose of this study was to evaluate the predictive performance of ultrasonography (US)-based radiomics for axillary lymph node metastasis and to compare it with that of a clinicopathologic model. Methods: A total of 496 patients (mean age, 52.5 +/- 10.9 years) who underwent breast cancer surgery between January 2014 and December 2014 were included in this study. Among them, 306 patients who underwent surgery between January 2014 and August 2014 were enrolled as a training cohort, and 190 patients who underwent surgery between September 2014 and December 2014 were enrolled as a validation cohort. To predict axillary lymph node metastasis in breast cancer, we developed a preoperative clinicopathologic model using multivariable logistic regression and constructed a radiomics model using 23 radiomic features selected via least absolute shrinkage and selection operator regression. Results: In the training cohort, the areas under the curve (AUC) were 0.760, 0.812, and 0.858 for the clinicopathologic, radiomics, and combined models, respectively. In the validation cohort, the AUCs were 0.708, 0.831, and 0.810, respectively. The combined model showed significantly better diagnostic performance than the clinicopathologic model. Conclusion: A radiomics model based on the US features of primary breast cancers showed additional value when combined with a clinicopathologic model to predict axillary lymph node metastasis.11Nsciescopu
Metabolic evaluation of children with global developmental delay
Global developmental delay (GDD) is a relatively common early-onset chronic neurological condition, which may have prenatal, perinatal, postnatal, or undetermined causes. Family history, physical and neurological examinations, and detailed history of environmental risk factors might suggest a specific disease. However, diagnostic laboratory tests, brain imaging, and other evidence-based evaluations are necessary in most cases to elucidate the causes. Diagnosis of GDD has recently improved because of remarkable advances in genetic technology, but this is an exhaustive and expensive evaluation that may not lead to therapeutic benefits in the majority of GDD patients. Inborn metabolic errors are one of the main targets for the treatment of GDD, although only a small proportion of GDD patients have this type of error. Nevertheless, diagnosis is often challenging because the phenotypes of many genetic or metabolic diseases often overlap, and their clinical spectra are much broader than currently known. Appropriate and cost-effective strategies including up-to-date information for the early identification of the "treatable" causes of GDD are needed for the development of well-timed therapeutic applications with the potential to improve neurodevelopmental outcomes
Current Researches on the Methods of Diagnosing Sasang Constitution: An Overview
Sasang constitution diagnosis has traditionally been conducted by a Sasang constitutional medicine (SCM) doctor who examines the external appearance, temperament and various symptoms of an individual and then collectively analyzes this information to determine their own constitutions. However, because this process is subjective and not quantitative, many researchers have been attempting to develop objective and reasonable methods of determining constitutions. In Korea, even though a wide range of research regarding SCM has been conducted, most of the work has not been revealed internationally. So in this review, the authors have searched the Journal of Sasang Constitutional Medicine, as well as other Korean domestic journal databases and Pubmed for research regarding modernized constitution diagnosis methods so to provide the understanding of current research state and outlook for future research
Fabrication of FeSe1-x superconducting films with bulk properties
We have fabricated high-quality FeSe1-x superconducting films with a bulk Tc
of 11-12 K on different substrates, Al2O3(0001), SrTiO3(100), MgO(100), and
LaAlO3(100), by using a pulsed laser deposition technique. All the films were
grown at a high substrate temperature of 610 oC, and were preferentially
oriented along the (101) direction, the latter being to be a key to fabricating
of FeSe1-x superconducting thin films with high Tc. According to the energy
dispersive spectroscopy data, the Fe:Se composition ratio was 1:0.90+-0.02. The
FeSe1-x film grown on a SrTiO3 substrate showed the best quality with a high
upper critical magnetic field [Hc2(0)] of 56 T
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