• Imaging Science in Dentistry
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• v.42 no.2
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• pp.111-114
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• 2012

Non-Hodgkin's lymphomas are a group of highly diverse malignancies and have a strong tendency to affect organs and tissues that do not ordinarily contain lymphoid cells. Primary extra nodal lymphoma of the hard palate is rare. Here, we present a case of diffuse large B cell lymphoma in a 60-year-old male patient that manifested as slightly painful ulcerated growth on the edentulous right maxillary alveolar ridge extending onto the palate, closely resembling carcinoma of the alveolar ridge. Computed tomography images showed the involvement of the maxillary sinus and right nasal cavity, along with destruction of hard palate, superiorly extending into the orbit. This case report highlights the importance of imaging to evaluate the exact extent of such large malignant lesions, which is essential for treatment planning.

• Journal of The Korean Astronomical Society
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• v.12 no.1
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• pp.27-34
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• 1979

Temperature history of very small interstellar dust particles is followed under diffuse interstellar radiation. Because of extremely small thermal capacities of these grains with sizes ranging from a few tens to hundred Angstroms in radii, they are to experience strong fluctuations in temperature whenever they are hit by interstellar ultraviolet photons. Fluctuating temperature can inhibit these smaller component of interstellar dust from growing into core-mantle particles of submicron sizes by continuously evaporating atoms and molecules adsorbed on their surface. This is interpreted as a possible physical reason for the bimodal nature in grain size distribution. A brief discussion is also given to the far infrared emission properties of such small grains in diffuse interstellar dust clouds.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.2
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• pp.301-312
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• 1996

A new approach is presented for recovering the 3-D shape from shading image. Photometric Stereo Method (PSM) is generally based on the direct illumination. In this paper, the reflectance function is derived by introduceing the indirect diffuse illumination in PSM and then applied to hybrid reflectance model which consists fo two components; the Lambertian reflectance and the speclar reflectance. Under the hybrid reflectance model and the indirect diffuse illumination circumstances, the 3-D shape of object can be recovered from the suface normal vector extracted from the surface roughness, the surface reflectance ratio, and the intensity value of a pixel. This method is rapid because of using the reference table and simplifies the restriction condition about the reflectance function existing in prior studies. The recovery efficiency in our method is better than that in prior studies. Also, this method is applied to various types of surfaces by defining general reflectance function.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.43 no.2
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• pp.138-143
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• 2017

Non-Hodgkin's lymphoma on the parotid gland is a relatively rare occurrence among head and neck tumors. The mass of parotid gland lymphoma cannot be distinguished from other benign masses of the parotid gland; therefore, it is important to consider lymphoma in the differential diagnosis when examining parotid swellings and masses. Parotid gland lymphoma is most likely to be B-cell, non-Hodgkin's lymphoma of one of three types, which include follicular, marginal zone, and diffuse large B-cell, although other histologic patterns have been described. We present a review of a patient with diffuse large B-cell lymphoma (DLBCL) who presented to the Department of Oral and Maxillofacial Surgery of Pusan National University Hospital (Yangsan, Korea).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.2A
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• pp.198-203
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• 2008

In this paper, we consider the diffuse type of indoor wireless optical communication (WOC) system. To find the channel characteristics of indoor wireless infrared communication system, we investigate the simulation process to get the impulse response of diffuse type and analyze the scenario of the indoor structure which we have built. The simulation results of the impulse response include power ratio and time delay due to bounce times. We get and discuss the receiving power distribution according to six configurations which have different transmitter and receiver positions and reflection coefficients of the indoor structure assumed. The results of this paper are useful to design the indoor wireless optical communication systems.

• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1832-1838
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• 2006

The present paper is focused on sorption concentration of silver (I) on some complex-forming ion exchangers in the initial thiocyanate form and subsequent determination of Ag(I) in the phase of anion exchanger AN-25 by diffuse reflectance spectroscopy. The sorption and kinetic characteristics of the sorbents were investigated. The apparent stability constants of thiocyanate silver complexes in the ion exchanger phase were calculated. The sorption-spectroscopic method is proposed for Ag(I) determination in aqueous solutions. The calibration curve is linear in the concentration range of 10-200 mg/L (sample volume is 10.0 mL) and the detection limit is 2 $\mu$g/mL. The presence of $Na^+,\;K^+,\;Mg^{2+}$ (macrocomponents) as well as of Ni (II), Co (II), Cu (II) do not hinder the determination of silver (I).

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.504-512
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• 2006

In order to estimate microbial contaminant discharge from diffuse sources, rainfall runoff was monitored at forestry, agriculture and urban watersheds. Total coliform and E. coli were monitored at the study watersheds as they are regulated by the environmental laws. Concentration and EMC (Event Mean Concentration) of coliform of rainfall runoff at the urban watershed were the highest followed by those from agricultural and forestry watersheds. By monitoring coliform concentrations of overlying water and sediment at five monitoring points in the downstream of the Geum River, average concentration from spring to summer was higher than those values from fall to spring. Coliform concentrations in the pore water were higher compared to those of overlying water and closely related with flow rate of the river.

• Journal of Korean Neurosurgical Society
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• v.39 no.6
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• pp.459-463
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• 2006

This report describes a case of diffuse neurofibroma[DNF] that presented with spontaneous intratumoral hemorrhage. A 31-year-old man with cutaneous manifestations typical of neurofibromatosis type 1[NF1] was referred to hospital with a progressively expanding scalp swelling. Magnetic resonance imaging[MRI] showed an acute hematoma surrounded by a dense mass on the parietooccipital scalp. Plain skull radiographs and a computed tomography[CT] scan revealed bony defects in the occipital bone around the lambdoid suture and the skull base, including the sphenoid and petrous bones. The tumor extended to the upper cervical region and infiltrated through the fascia of the musculature. The tumor and adjacent soft tissue were highly vascular, which made surgical resection difficult. We describe the clinical, radiological and pathological features of this patient md discuss the surgical methods used to avoid a life-threatening hemorrhage during surgery.

• Tuberculosis and Respiratory Diseases
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• v.84 no.4
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• pp.255-262
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• 2021

Microscopic polyangiitis (MPA) is an antineutrophil cytoplasmic antibody (ANCA)-associated necrotizing vasculitis, which mainly affects small vessels in various organs, especially the lungs. The two key pulmonary manifestations, interstitial lung disease (ILD) and diffuse alveolar hemorrhage (DAH), increase the morbidity and death rate of patients with MPA. ILD is more common in MPA than in other ANCA-associated vasculitis subsets and is primarily associated with myeloperoxidase-ANCA. Unlike alveolar hemorrhage due to pulmonary capillaritis, ILD can initially manifest as isolated pulmonary fibrosis. Of note, its most frequent radiographic pattern is the usual interstitial pneumonia pattern, similar to the characteristic pattern seen in idiopathic pulmonary fibrosis. In this review we present the pathogenesis, clinical manifestations, and radiographic and histopathologic features of ILD and DAH in MPA. We also briefly summarize the outcome and therapeutic options for the two conditions.

• Annals of Clinical Neurophysiology
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• v.24 no.2
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• pp.79-83
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• 2022

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin's lymphoma. Although progressive lymphadenopathy is a typical feature, extranodal involvement may also occur, including the gastrointestinal tract, skin, bone, thyroid, and testes. Central nervous system invasion is rare, so differentiating it from diseases such as inflammatory demyelinating disorder or infection is essential. DLBCL is therefore a challenge to diagnose, especially when the first findings are neurological symptoms. We report an unusual case of DLBCL that presented as transverse myelitis.