표백에 의한 라디에타소나무의 청변 제거

김규혁,김형준,나종범,김재진 한국목재공학회 2003 목재공학 Vol.31 No.1

본 연구는 라디에타소나무 제재목의 균 변색을 제거하기 위한 표백처리의 사용 가능성을 조사하기 위하여 수행하였다. 염소계 표백제인 아염소산나트륨과 차아염소산나트륨은 표백조건(약제농도, 처리온도, 처리시간)의 조절에 따라 만족할만한 변색제거 효과를 얻을 수 있었다. 비염소계 표백제인 과산화수소는 표백조건의 조절만으로는 변색제거가 불가능하였으나 규산나트륨과 수산화나트륨을 활성제로 첨가하는 경우에는 염소계 표백제보다 탁월한 변색제거 효과를 나타내었다. 그러나 활성제 첨가에 따라 재색의 녹색화 문제가 발생하였는데, 앞으로 이러한 문제점을 해결하기 위한 연구가 진행되어야 할 것이다. 또한, 앞으로 본 연구를 통해 개발된 변색제거방법의 현장 적용을 후속 연구도 필요하다고 본다. The feasibility of using bleaching treatments for removing fungal stain was evaluated on heavily stained raiadta pine sapwood. Sodium chlorite and sodium hypochlorite appeared to destain fungal discoloration by providing proper treatment conditions (chemical concentration, treatment temperature, and treatment time), while hydrogen peroxide did not remove fungal stain under the bleaching regimes evaluated. The addition of sodium silicate and sodium hydroxide in the hydrogen peroxide solution as a buffer could remove fungal discoloration completely:; however, the color of wood surface turned faint green after bleaching, thereby reducing the lightness of bleached samples. The results suggest that hydrogen peroxide bleaching could be a feasible method for removing fungal discoloration of stained radiata pine sapwood, although further research is needed to solve the problem of color change after bleaching Also, further tests under field conditions are recommended.

소나무와 잣나무 원목에서 변재변색 발생

김규혁,김재진,나종범 한국목재공학회 2002 목재공학 Vol.30 No.2

본 연구는 동절기 (1월 중순)에 벌채된 후 목재집하장으로 운반되어 야적장에 저목 중인 소나무와 잣나무 원목을 대상으로 변재변색의 발생시기와 변색 특성을 조사하기 위하여 수행되었다. 벌채 후 3, 4, 5, 6, 8개월 경과시 변색 평가를 실시하였는데, 매 평가시 원목 3개를 임의로 선정하여 원목당 수축방향에 대해 일정 간격으로 7∼9개의 두께 3 ㎝ 원판을 채취하여 변색 원인균을 분리한 후 변재변색의 방사방향 최대 침투깊이와 % 변색율을 측정하였다. 변재변색은 전적으로 층형변색이었으며, 주요 변색원인균인 Ophiostomatoid 균을 매개하는 수피천공충은 소나무좀으로 확인되었다. 소나무와 잣나무 원목은 5월 이전까지는 변재변색의 위험없이 저목할 수 있으나 5월 이후부터는 원목의 변재변색이 급속하게 증가하였다. 변색의 정도는 소나무보다 잣나무에서 심하였으며, 장마철 저목 중에 소나무 원목에서 개떡버섯과 치마버섯의 자실체를 다수 관찰할 수 있었다. 본 연구를 통해 밝혀진 결과들은 앞으로 동절기에 벌채되어 저목 중인 소나무와 잣나무 원목에 발생하는 변재변색을 예방하기 위한 제반 조치를 취하는데 매우 중요한 자료로 사용될 것이다. This study was conducted to investigate the influence of storage time on the sapstain development of Japanese red pine and Korean pine logs during storage in log yard, and their stain characteristics. Japanese red pine and Korean pine trees were harvested and cut into logs in mid January of 2001. These logs were transported to the two local sawmills where they were closely stacked in remote parts of log yard. The logs were then sampled destructively by cutting seven to nine 3-㎝ long discs along the length of each log at intervals of 3, 4, 5, 6, and 8 month after felling. The stain coverage and maximal radial penetration of stain were measured from the discs of the sampled logs after the isolation of causal staining fungi. The sapstain was primarily infested by the attack of bark beetles and the species of bark beetle was identified as Tomicus piniperda. The main fungal species isolated from stained wood was Ophiostoma species. Based on the present study, the logs could be stored in log yard until May without stain; but stain development was rapid after May and the severity of stain increased proportionally with storage time. Korean pine was more susceptible to fungal stain than Japanese red pine. During summer storage, decay started to develop in logs and the main species were identified as Tyromyces sp. and Schizophyllum commune. Information provided in this paper would be very useful to develop more effective control strategies for sapstain prevention in Japanese red pine and Korean pine logs.

CCA 처리재로부터 방부제 유효성분의 용제추출

김규혁,공일곤,나종범,조재성,김재진 한국목재공학회 2003 목재공학 Vol.31 No.4

본 연구는 CCA 처리재로부터 방부제 유효성분을 추출하기 위한 적정 용제를 선정하고, 선정된 용제의 최적추출조건을 평가하기 위 해 수행되었다. 추출수율과 용제의 사용 및 환경 안전성을 고려할 때, 과산화수소가 CCA유효성분을 추출하는 데 가장 적절한 용제로 선정되었다. 과산화수소를 이용한 추출 결과. 추출온도, 추출용제농도, 추출시간 간에 상호작용이 존재하였으나 추출온도와 추출용제의 농도가 높을수록, 그리고 추출시간이 연장될수록 CCA유효성분의 추출수율은 증가되었다. 경제적인 측면을 고려할 때 가능하면 낮은 농도의 추출용제를 사용하여 저온에서 추출하여야 하나, 이 경우에는 필요한 추출수율을 달성하기 위한 추출시간이 상당히 길어지기 때문에 40℃ 이상의 온도에서 추출이 바람직하며 사용할 추출용제의 농도는 추출시간을 고려하여 최종적으로 결정하여야 된다고 사료된다. This research was performed to select an appropriate agent to extract preservative components from CCA-treated wood, and then to evaluate the effect of reagent concentration, extracting temperature, and CCA-treated wood, and then to evaluate the effect of reagent concentration, extracting temperature, and extracting time on the removal of chrome, copper, and arsenic from treated wood. Hydrogen peroxide was selected as the best extracting agent when considered extraction yield as well as use and environmental safety. Its extraction yield was dependent on extracting variables (temperature, concentration, and time), and a highly significant interaction existed among variables. It should be possible to optimize extraction by manipulating these extracting variables. The results may suggest that the required temperature conditions for the reasonable removal of CCA components are at least above 40℃ because extracting time is too long at low temperature (20℃). Reagent concentrations for extracting at above 40℃ should be decided by considering the extracting time.

수액치한법을 이용한 소경재의 산지처리(Ⅰ) : 증산법과 원구법을 이용한 처리 가능성 Feasibility of Treatment Using Transpiration Method and Butt-end Method

전수경,김재진,나종범,김규혁 한국목재공학회 2002 목재공학 Vol.30 No.4

본 연구는 수액치환법을 이용한 침엽수 간벌소경재나 미(저)이용 활용수재의 산지 보존처리 기술을 개발하기 위하여 수행되었다. 본 논문에서는 증산법과 원구법을 이용한 3종 침엽수와 3종 활엽수의 방부제, 난연제, 치수안정제 처리 가능성을 조사하여 보고한다. 수종과 처리약제의 조합에 관계없이 원구법이 증산법에 비하여 약제의 목재내 침투가 양호할 뿐만 아니라 약제의 침투가 균일한 관계로 수분 이동경로를 이용한 처리재 생산은 원구법의 사용이 바람직하였다. 원구법 처리는 수관부를 절단한 후 실시하기 때문에 증산법에 비하여 처리가 용이할 뿐만 아니라 벌채 및 조재 후 산지의 일정 장소로 운재 후 처리를 실시하기 때문에 증산법과 비교할 때 집약적 처리로 단위시간당 처리재 생산량이 높고 산지 환경오염 문제도 예방할 수 있는 장점이 있다. This research was carried out to develop field treatment techniques of thinned small diameter softwood logs and less utilized hardwood logs using sap displacement method. In this paper, we report the feasibility of using transpiration method and butt-end method for the treatment of three softwood species and three hardwood species with preservatives, fire-retardant chemicals, and dimensional stabilizer. Butt-end method was effective as a field treatment technique compared to transpiration method when considered the treatability, easiness of treatment, productivity of treated wood, and environmental aspects related to chemical treatment, regardless of the combination of wood species and chemicals.

단무지 공장에서 발생한 질식 사고의 원인과 방사선학적 소견: 중례보고 및 가스분석 결과

박충기,김만구,김흥철,안범규,박만수,황우철,최철순,강익원 江原大學校 附設 環境硏究所 1994 環境硏究 Vol.11 No.-

목 적:단무지 공장에서 질식사고를 일으켰던 가스의 종류를 알아내고, 이러한 가스중독의 방서선학적 소견을 소개하기 위하여 본 연구를 하였다. 대상 및 방법:단무지 공장에서 발생한 질식 사고자 3예중 생존자 1예를 대상으로 단순흥부X-선검사와 CT 소견을 분석하였으며, 가스의 종류를 알아내기 위하여 단무지를 유리병에 넣어 발생된 가스를 가스크로마토그래픽을 이용하여 분석하였다. 결 과:단무지 공장에서 발생한 질식사고자중 생존한 1명의 방사선학적 검사에서 신속히 호전되는 폐경결(consolidation)을 볼 수 있었으며 이는 폐부종의 소견임을 알 수 있었다. 협기성 상태에서 단무지를 담은 유리병의 상층부 가스를 실험 분석한 결과 이산화탄소, 에칠알코올이 다량으로 검출되었으나 독성가스는 주로 황화수소이였다. 결 론:단무지 공장의 질식 사고자에서 폐방사선학적 소견은 폐경결을 보이는 폐부증으로서 이는 실험을 통해 단무지에서 발생되는 유독가스인 황화수소 때문임을 입증하였다. Purpose: To identify the main toxic gas released from salted radish in rice bran(Dan-M-Ji) and to introduce the radiological findings of the patient who was exposed to the gas. Materials and Methods: Chest radiographs and CT scans of one survivor among three men who were exposed to the gas from Dan-Mu-Ji were reviewed. Gas obtained from the closed bottle containing Dan-Mu-Ji was analized by using the gas chromatography. Results: The radiographlc examinations of the survivor were suggestive of pulmonary edema with it's rapidly improving consolidations in both lung. The headapace gas within the bottle containing Dan-Mu-Ji was mainly composed with carbon dioxide, ethyl alcohol and hydrogen sulfide, of which hydrogen sulfide was considered the main toxic gas released. Conclusion: Under the anaerobic condition, Dan-Mu-Ji released toxic hydrogen sulfide. Inhalation of hydrogen sulfide might produce non-cardiogenic pulmonary edema.

연약한 점성토 지반의 지지력 결정에 관한 연구

안종필,박상범,김규덕 朝鮮大學校 建設技術硏究所 2004 建設技術硏究 Vol.24 No.2

To find out the variation of bearing capacity due to the plasticity of soils in case of working the unsymmetrical surcharge of ML, CL, and CH, the existing theoretic expression were investigated and were compared with a series of test results The critical surcharge of soft soils was found as q_(cr)=4.22C_(u) in ML, which is slightly larger than the existing expression, but similar to Darragh's expression. The critical surcharge in CL was found as q_(cr)=3.21C_(u), which is the value between JHI and Jaky and in CH was found as qcr=2.60C_(u), which is a the value between Tachebotarioff and Meyerhof. The ultimate bearing capacity of soft soils was found as q_(uIt) = 11.19C_(u) in ML, which was significantly larger than the existing expression. The ultimate bearing capacity of CL was found as q_(ult)=8.41C_(u), which was slightly bigger than the existing expression, but is close to Meyerhof's expression. The ultimate bearing capacity in CH was found as q_(uIt) =4.73C_(u), which is similar to Parndtl's expression.

측두골 골절 : 임상적 및 방사선학적 분석 Clinical and Radiological Analysis

조성원,최순관,조성진,김범태,신원한,윤일규,변박장 순천향의학연구소;Soonchunhyang Medical Research Institute 2000 Journal of Soonchunhyang Medical Science Vol.6 No.1

The objective of this study is to review of the incidence of temporal bone fractures and complications resulting from temporal bone fractures and to analyze the correlation between clinical and radiological findings. A series of 49 patients who were diagnosed temporal bone fracture with rhinorrhea, bloody otorrhea, admitted to Soonchunhyang University Chon-an Hospital from January 1997 to September 1999, were studied retrospectively. Clinical analyses were focused on age, sex, type of accident, external wound site, CSF leakage, hearing loss and facial nerve palsy. The high resolution CT scan consisted of a series of 3-mm thick sections through the temporal bone using the GE CT scanner (General Electric Inc.). In radiologic analyses, fracture types of temporal bone were divided into longtudinal fracture(LF), transverse fracture(TF) and mixed fracture(MF) respectively. The CT scans were examined for mastoid antral haziness(MH), middle ear cavity haziness(MeH), ossicular chain disruption(OD), otic capsule fracture(OF), pneumocephalus(Pn). The type of facial canal fracture was classified as fracture of internal auditory canal portion(FIAC), fracture of perigeniculate portion(FPG), fracture of tympanic portion(FT), fracture of mastoid portion(FM). The correlation between clinical and radiological findings was analysed. A total of 49 fractured temporal bones resulted in 9 CSF fistula, 23 hearing loss( 13 conductive type, 7 sensorineural type), 17 facial nerve injuries ranging from mild paresis to complete paralysis. The mose common etiology of the injury was from a motor vehicle accident(28%). The type of fracture observed on high resolution CT scanning was a LF in 39(78%) patients, a TF in 7(14%) patients and a MF in 3(6%) patients. The majority of fractures terminate in the floor of the middle cranial fossa in LF and passed lateral to the otic capsule in TF. Average time of onset of delayed facial palsy was 3.5 days. No patient developed prolonged otorrhea or meningitis during hospitalization and there was no requirement of surgical management. Hearing loss was the most common complication of temporal bone fracture(48%). Conductive hearing loss was associated with middle ear cavity haziness and ossiclular chain disruption. in temporal bone CT. A total of 29 cases facial canal fracture in temporal bone CT resulted in 14 perigeniculate portion(FPG), 12 tympanic portion(FT), 3 mastoid portion(FM). There was no correlation between radiological facial canal fracture and clinical facial nerve palsy. Four of 17 patients with facial nerve injury required facial nerve exploration under general anesthesia. We thought that prognosis and therapeutic planning in patients with temporal bone fractures were based on the clinical and radiological findings.

3D cell printing of <i>in vitro</i> stabilized skin model and <i>in vivo</i> pre-vascularized skin patch using tissue-specific extracellular matrix bioink: A step towards advanced skin tissue engineering

Kim, Byoung Soo,Kwon, Yang Woo,Kong, Jeong-Sik,Park, Gyu Tae,Gao, Ge,Han, Wonil,Kim, Moon-Bum,Lee, Hyungseok,Kim, Jae Ho,Cho, Dong-Woo Elsevier 2018 Biomaterials Vol.168 No.-

<P><B>Abstract</B></P> <P>3D cell-printing technique has been under spotlight as an appealing biofabrication platform due to its ability to precisely pattern living cells in pre-defined spatial locations. In skin tissue engineering, a major remaining challenge is to seek for a suitable source of bioink capable of supporting and stimulating printed cells for tissue development. However, current bioinks for skin printing rely on homogeneous biomaterials, which has several shortcomings such as insufficient mechanical properties and recapitulation of microenvironment. In this study, we investigated the capability of skin-derived extracellular matrix (S-dECM) bioink for 3D cell printing-based skin tissue engineering. S-dECM was for the first time formulated as a printable material and retained the major ECM compositions of skin as well as favorable growth factors and cytokines. This bioink was used to print a full thickness 3D human skin model. The matured 3D cell-printed skin tissue using S-dECM bioink was stabilized with minimal shrinkage, whereas the collagen-based skin tissue was significantly contracted during <I>in vitro</I> tissue culture. This physical stabilization and the tissue-specific microenvironment from our bioink improved epidermal organization, dermal ECM secretion, and barrier function. We further used this bioink to print 3D pre-vascularized skin patch able to promote <I>in vivo</I> wound healing. <I>In vivo</I> results revealed that endothelial progenitor cells (EPCs)-laden 3D-printed skin patch together with adipose-derived stem cells (ASCs) accelerates wound closure, re-epithelization, and neovascularization as well as blood flow. We envision that the results of this paper can provide an insightful step towards the next generation source for bioink manufacturing.</P>

Luminescence Properties of Si Nanocrystals Fabricated by Ion Beam Sputtering and Annealing

Kim, Sung,Shin, Dong Hee,Shin, Dong Yeol,Kim, Chang Oh,Park, Jae Hee,Yang, Seung Bum,Choi, Suk-Ho,Yoo, Seung Jo,Kim, Jin-Gyu Hindawi Limited 2012 Journal of nanomaterials Vol.2012 No.-

<P>During the past several decades, Si nanocrystals (NCs) have received remarkable attention in view of potential optoelectronic device applications. This paper summarizes recent progress in the study of luminescence from Si NCs, such as photoluminescence (PL), cathodoluminescence, time-solved PL, and electroluminescence. The paper is especially focused on Si NCs produced by ion beam sputtering deposition of<SUB>SiOx</SUB>single layer or<SUB>SiOx</SUB>/SiO2multilayers and subsequent annealing. The effects of stoichiometry (x) and thickness of Si<SUB>Ox</SUB>layers on the luminescence are analyzed in detail and discussed based on possible mechanisms.</P>

Reference ranges for induced sputum eosinophil counts in Korean adult population

Kim, Mi-Yeong,Jo, Eun-Jung,Lee, Seung-Eun,Lee, Suh-Young,Song, Woo-Jung,Kim, Tae-Wan,Hur, Gyu-Young,Lee, Jae-Hyung,Kim, Tae-Bum,Park, Heung-Woo,Chang, Yoon-Seok,Park, Hae-Sim,Min, Kyung-Up,Cho, Sang-H Asia Pacific Association of Allergy, Asthma and Cl 2014 Asia Pacific allergy Vol.4 No.3

<P><B>Background</B></P><P>Induced sputum analyses are widely utilized to evaluate airway inflammation in asthmatics. However, the values have not been examined in Korean adults.</P><P><B>Objective</B></P><P>The purpose of this study is to determine reference ranges for induced sputum eosinophils and their influencing factors in Korean adults.</P><P><B>Methods</B></P><P>A total of 208 healthy nonasthmatic adults were recruited. Sputum induction and processing followed the international standard protocols.</P><P><B>Results</B></P><P>Adequate sputum samples were successfully collected from 81 subjects (38.9%). The upper 90 percentile for sputum eosinophil was calculated as 3.5%. The median value of eosinophil count percentage was significantly higher in subjects with atopy than those without atopy (median, 1.6%; range, 0-11.0% vs. median, 0%; range 0-3.6%, <I>p</I>=0.030). However, no significant correlations were found with age, gender, body mass index, smoking status, blood eosinophil, or fractional exhaled nitric oxide levels.</P><P><B>Conclusion</B></P><P>Current study was the first attempt to determine the reference ranges of induced sputum eosinophils in Korean adults. The cutoff value for sputum eosinophilia was 3.5%, and was significantly associated with atopy.</P>