420 research outputs found
Formation of ZnO Micro-Flowers Prepared via Solution Process and their Antibacterial Activity
This paper presents the fabrication and characterization of zinc oxide micro-flowers and their antibacterial activity. The micro-flowers of zinc oxide composed of hexagonal nanorods have been prepared via solution process using precursor zinc acetate di-hydrate and sodium hydroxide in 3 h of refluxing time at ~90ยฐC. The antibacterial activities of grown micro-flowers were investigated against four pathogenic bacteria namely S. aureus, E. coli, S. typhimurium and K. pneumoniae by taking five different concentrations (5โ45 ฮผg/ml) of ZnO micro-flowers (ZnO-MFs). Our investigation reveals that at lowest concentration of ZnO-MFs solution inhibiting the growth of microbial strain which was found to be 5 ฮผg/ml for all the tested pathogens. Additionally, on the basis of morphological and chemical observations, a chemical reaction mechanism of ZnO-MFs composed of hexagonal nanorods was also proposed
Proteomic Validation of Multifunctional Molecules in Mesenchymal Stem Cells Derived from Human Bone Marrow, Umbilical Cord Blood and Peripheral Blood
Mesenchymal stem cells (MSCs) are one of the most attractive therapeutic resources in clinical application owing to their multipotent capability, which means that cells can differentiate into various mesenchymal tissues such as bone, cartilage, fat, tendon, muscle and marrow stroma. Depending on the cellular source, MSCs exhibit different application potentials according to their different in vivo functions, despite similar phenotypic and cytological characteristics. To understand the different molecular conditions that govern the different application or differentiation potential of each MSC according to cellular source, we generated a proteome reference map of MSCs obtained from bone marrow (BM), umbilical cord blood (CB) and peripheral blood (PB). We identified approximately 30 differentially regulated (or expressed) proteins. Most up-regulated proteins show a cytoskeletal and antioxidant or detoxification role according to their functional involvement. Additionally, these proteins are involved in the increase of cell viability, engraftment and migration in pathological conditions in vivo. In summary, we examined differentially expressed key regulatory factors of MSCs obtained from several cellular sources, demonstrated their differentially expressed proteome profiles and discussed their functional role in specific pathological conditions. With respect to the field of cell therapy, it may be particularly crucial to determine the most suitable cell sources according to target disease
Patterns of Using Complementary and Alternative Medicine by Stroke Patients at Two University Hospitals in Korea
This study measured the prevalence of complementary and alternative medicine (CAM) use among Korean stroke patients. Questionnaire-based 20-min interviews were conducted at the hospitals by a trained nurse after an outpatient visit. It included questions on demographic information, clinical information and the utilization of CAM. Of 304 stroke-patient respondents, 164 (54%) had used CAM, of which 66% had started taking CAM products following suggestions from family members and other relatives. Of the 57% of users who felt that CAM was effective, 84% considered that it improved the symptoms of stroke and 16% felt it was effective in achieving psychological relaxation. Of the eight CAM categories used by respondents, 92% used traditional Oriental medical treatments, 36% used plant- and animal-derived over-the-counter health care products, 24% used minerals and vitamins, and 11% used manual therapies. The majority of stroke patients (68%) were trying a new type of CAM, and half of the respondents (45%) relied on the knowledge of their general practitioner about CAMs when deciding whether to use them. Most of the stroke patients in this study used CAM, and a half of them reported beneficial effects. Despite the presence of adverse side effects, they tended to be used without discussion with chief physicians, and hence physicians should be actively involved in the usage of CAM
Evaluation of the brain activation induced by functional electrical stimulation and voluntary contraction using functional magnetic resonance imaging
BACKGROUND: To observe brain activation induced by functional electrical stimulation, voluntary contraction, and the combination of both using functional magnetic resonance imaging (fMRI). METHODS: Nineteen healthy young men were enrolled in the study. We employed a typical block design that consisted of three sessions: voluntary contraction only, functional electrical stimulation (FES)-induced wrist extension, and finally simultaneous voluntary and FES-induced movement. MRI acquisition was performed on a 3.0โT MR system. To investigate activation in each session, one-sample t-tests were performed after correcting for false discovery rate (FDR; pโ<โ0.05). To compare FES-induced movement and combined contraction, a two-sample t-test was performed using a contrast map (pโ<โ0.01). RESULTS: In the voluntary contraction alone condition, brain activation was observed in the contralateral primary motor cortex (MI), thalamus, bilateral supplementary motor area (SMA), primary sensory cortex (SI), secondary somatosensory motor cortex (SII), caudate, and cerebellum (mainly ipsilateral). During FES-induced wrist movement, brain activation was observed in the contralateral MI, SI, SMA, thalamus, ipsilateral SII, and cerebellum. During FES-induced movement combined with voluntary contraction, brain activation was found in the contralateral MI, anterior cingulate cortex (ACC), SMA, ipsilateral cerebellum, bilateral SII, and SI. The activated brain regions (number of voxels) of the MI, SI, cerebellum, and SMA were largest during voluntary contraction alone and smallest during FES alone. SII-activated brain regions were largest during voluntary contraction combined with FES and smallest during FES contraction alone. The brain activation extent (maximum t score) of the MI, SI, and SII was largest during voluntary contraction alone and smallest during FES alone. The brain activation extent of the cerebellum and SMA during voluntary contraction alone was similar during FES combined with voluntary contraction; however, cerebellum and SMA activation during FES movement alone was smaller than that of voluntary contraction alone or voluntary contraction combined with FES. Between FES movement alone and combined contraction, activated regions and extent due to combined contraction was significantly higher than that of FES movement alone in the ipsilateral cerebellum and the contralateral MI and SI. CONCLUSIONS: Voluntary contraction combined with FES may be more effective for brain activation than FES-only movements for rehabilitation therapy. In addition, voluntary effort is the most important factor in the therapeutic process
Pose-Aware Instance Segmentation Framework from Cone Beam CT Images for Tooth Segmentation
Individual tooth segmentation from cone beam computed tomography (CBCT)
images is an essential prerequisite for an anatomical understanding of
orthodontic structures in several applications, such as tooth reformation
planning and implant guide simulations. However, the presence of severe metal
artifacts in CBCT images hinders the accurate segmentation of each individual
tooth. In this study, we propose a neural network for pixel-wise labeling to
exploit an instance segmentation framework that is robust to metal artifacts.
Our method comprises of three steps: 1) image cropping and realignment by pose
regressions, 2) metal-robust individual tooth detection, and 3) segmentation.
We first extract the alignment information of the patient by pose regression
neural networks to attain a volume-of-interest (VOI) region and realign the
input image, which reduces the inter-overlapping area between tooth bounding
boxes. Then, individual tooth regions are localized within a VOI realigned
image using a convolutional detector. We improved the accuracy of the detector
by employing non-maximum suppression and multiclass classification metrics in
the region proposal network. Finally, we apply a convolutional neural network
(CNN) to perform individual tooth segmentation by converting the pixel-wise
labeling task to a distance regression task. Metal-intensive image augmentation
is also employed for a robust segmentation of metal artifacts. The result shows
that our proposed method outperforms other state-of-the-art methods, especially
for teeth with metal artifacts. The primary significance of the proposed method
is two-fold: 1) an introduction of pose-aware VOI realignment followed by a
robust tooth detection and 2) a metal-robust CNN framework for accurate tooth
segmentation.Comment: 10 pages, 10 figure
Continuous process of carbon nanotubes synthesis by decomposition of methane using an arc-jet plasma
Author's version; The Joint Meeting of 7th APCPST (Asia Pacific Conference on Plasma Science and Technology) and 17th SPSM (Symposium on Plasma Science for Materials) - 7th APCPST/17th SPSMWe present a method of producing carbon nanotubes by means of the thermal plasma decomposition of methane in an arc-jet plasma of high temperature (5000โ20,000 K). Carbon nanotubes are produced under a floating condition by introducing methane and a mixture of NiโY powders into the arc-jet plasma flame generated by a non-transferred plasma torch. Material evaluations of the synthesized product by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) reveal that the growth rate of carbon nanotubes is very high, and that the multi-walled carbon nanotubes of high purity are mainly produced. Since this process is continuously operable and easily scalable, it is expected to be a promising technique for large-scale commercial production of carbon nanotubes.Korea Institute of Science and Technology Evaluation and Planning (KISTEP
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