1,529 research outputs found
Differentiating the Impact of Nitrogen Chemical States on Optical Properties of Nitrogen-Doped Graphene Quantum Dots
The optical properties of top-down synthesized oxidized graphene quantum dots (ox-GQDs) and nitrogen-incorporating graphene quantum dots (N-GQDs) along a range of hydrothermal treatment temperatures were observed. By controlling the hydrothermal treatment temperature, different chemical states of nitrogen atoms were incorporated into GQDs. Below 150 °C, edge-terminating amines and amides dominated the nitrogen content of N-GQDs. Above 150 °C, nitrogen was primarily present in the forms of pyridinic, pyrrolic and quaternary N. In addition to the absorbance and emission profiles of ox-GQDs and N-GQDs, pH-dependent emission spectra were collected to probe chemical states of nitrogen atoms and investigate the relationship between nitrogen location and photoluminescence
Superficial cervical plexus block for management of herpes zoster neuralgia in the C3 dermatome: a case report
INTRODUCTION: Herpes zoster is a well-known reactivating viral disease that gives rise to painful skin lesions. Although this vesicular rash heals up within a few weeks, pain sometimes continues, becoming postherpetic neuralgia. In the case of those at high risk of developing postherpetic neuralgia, early interventional pain management is generally recommended as a preventive measure. Pain specialists usually do not see patients face-to-face for chronic refractory pain until the stage of postherpetic neuralgia. However, active and aggressive management, including antiviral treatment, of herpetic neuralgia during the acute stage of herpes zoster promises better results. In this respect, superficial cervical plexus block can help patients, such as the case reported here, by relieving the pain of herpes zoster involving the C3 dermatome. CASE PRESENTATION: A 65-year-old Korean man with severe pain in his left C3 dermatome due to herpes zoster was admitted to our hospital. His pain was so refractory to medication that he consulted our pain clinic for pain control. Due to the medication limitations imposed by his underlying diseases (hepatitis B, liver cirrhosis, atrial fibrillation, and asthma), early interventional therapy including stellate ganglion block was planned. In addition, because his painful C3 dermatome overlapped significantly with the superficial cervical plexus dermatome, ultrasound-guided superficial cervical plexus block was utilized for pain control of the intractable herpes zoster neuritis in his C3 dermatome. The result with respect to his sporadic neuralgia was satisfactory. CONCLUSIONS: We found superficial cervical plexus block to be an effective interventional procedure for pain management of herpes zoster, particularly at the C3-dermatomal level
Permeability Enhancement in PorousâSintered ReactionâBonded Silicon Nitrides
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87172/1/j.1744-7402.2010.02511.x.pd
Automatic segmentation of large bowl obstruction area with hough transform from erect abdominal radiograph images
Large bowel obstruction is less frewuent but often appears acute and needs emergent treatment. Erect abdominal radiograph is usually the first imaging study performed in patients suspected of having large bowel obstruction. However, that mordality suffers from operator subjectivity thus a fully automatic computer aied tool is necessary. In this paper, we peopose an automatic large bowel feature (air-fluid region) segmentation method based on Canny edge detection and Hough transform. In experiment, the proposed method was successful in finding target region from large bowel obstruction patientsâ radiographic images in all 30 cases provided. Whilie limited only applicable to the large bowel obstruction cases, the proposed method is practically feasible in application
Study of orientation effect on nanoscale polarization in BaTiO3 thin films using piezoresponse force microscopy
We have investigated the effect of texture on in-plane (IPP) and out- of plane (OPP) polarizations of pulsed-laser-deposited BaTiO3 thin films grown on Pt and La0.5Sr0.5CoO3 (LSCO) buffered Pt electrodes. The OPP and IPP polarizations were observed by piezoresponse force microscopy (PFM) for three-dimensional polarization analyses in conjunction with conventional diffraction methods using x-ray diffraction and reflection high energy electron diffraction measurements. BaTiO3 films grown on Pt electrodes exhibited highly (101) preferred orientation with higher IPP component whereas BaTiO3 film grown on LSCO/Pt electrodes showed (001) and (101) orientations with higher OPP component. Measured effective d(33) values of BaTiO3 films deposited on Pt and LSCO/ Pt electrodes were 14.3 and 54.0 pm/ V, respectively. Local piezoelectric strain loops obtained by OPP and IPP-PFM showed that piezoelectric properties were strongly related to film orientation
Generalizations of Choi's Orthogonal Latin Squares and Their Magic Squares
Choi Seok-Jeong studied Latin squares at least 60 years earlier than Euler.
He introduced a pair of orthogonal Latin squares of order 9 in his book.
Interestingly, his two orthogonal non-diagonal Latin squares produce a magic
square of order 9, whose theoretical reason was not studied. There have been a
few studies on Choi's Latin squares of order 9. The most recent one is Ko-Wei
Lih's construction of Choi's Latin squares of order 9 based on two
orthogonal Latin squares. In this paper, we give a new generalization of Choi's
orthogonal Latin squares of order 9 to orthogonal Latin squares of size
using the Kronecker product including Lih's construction. We find a geometric
description of Chois' orthogonal Latin squares of order 9 using the dihedral
group . We also give a new way to construct magic squares from two
orthogonal non-diagonal Latin square, which explains why Choi's Latin squares
produce a magic square of order 9.Comment: 18 pages revised slightly from Dec. 5, 2018 versio
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