K-IFRS 도입에 따른 이익공시후 주가표류현상의 특성에 대한 분석: 연결재무제표이익과 별도재무제표이익의 차이를 중심으로

박석진,이은철 한국회계학회 2015 회계저널 Vol.24 No.6

Korea made International Financial Reporting Standards(IFRS) application mandatory for all listed companies in Korea effective from 2011. Under IFRS, according to whether entities have subsidiaries or not, they prepare three types of financial statements. One is individual financial statements, another is consolidated financial statements, and the other is separate financial statements. As for the controlling entities that prepare consolidated financial statements, they are required to prepare separate financial statements together with the consolidated financial statements in accordance with IFRS. While consolidated financial statements present the financial position and operating results for a parent company and its subsidiaries as if they were a single economic entity, separate financial statements are financial statements prepared by a parent, or an investor in a joint venture etc., where those investments are accounted for either at cost or fair value. Before IFRS adoption, individual financial statements are primary financial statements in Korea. Under IFRS, an entity that does not have a subsidiary prepares individual financial statements. However, as for the entities having one or more subsidiaries, consolidated financial statements are prepared as primary financial statements and separate financial statements are treated as supplementary financial statements under IFRS regime. Unlike separate financial statements, individual financial statements are financial statements that investments in associates are required to be accounted for using the equity method. Investors who familiar with individual financial statements might be confused with the information contents disclosed in separate financial statements and consolidated financial statements. Especially the difference between separate and consolidated earnings may cause confusion in making decisions by information users. This confusion can be explained by the hypothesis of functional fixation. Functional fixation hypothesis is that individual investors interpret earnings numbers the same way regardless of the accounting procedure used to calculate them, so there would be mechanical relation between earnings and stock prices(Watts and Zimmerman 1986). According to Watts and Zimmerman’s interpretation, the functional fixation hypothesis is that investors do not discriminate between earnings calculated using different procedures because it is costly to adjust the numbers or investors are irrational. This study examines whether the difference between separate and consolidated earnings is associated with post earnings announcement drift(PEAD). PEAD is the tendency for stock’s cumulative abnormal returns to drift in the direction of the earnings surprise after earnings announcement. PEAD is considered as one of the market anomaly that is in a conflict with semi-strong efficient market hypothesis. This phenomenon was first discovered by Ball and Brown(1968). They reported that stock returns continue to drift in the direction of earnings surprise for several months after earnings announcements. If investors are confused with entity’s information, the stock price reaction to earnings announcements may not fully reflect the information contained in the earnings announcement. In this paper, We analyze 1,466 non-financial and December year-end firm/year observations listed in the KOSPI market. Sample period spans from 2012 to 2014. Our hypothesis is that the difference between separate and consolidated earnings is positively related with PEAD. The difference between separate and consolidated earnings is measured in two ways. One is the difference between separate and consolidated unexpected earnings, the other is the difference between separate and consolidated earnings per share. We find following empirical results. The level of PEAD and the difference between separate and consolidated earnings has positive relation. This result implicates that consolidated finan... 본 연구는 2011년 국제회계기준 도입 이후 연결재무제표가 주재무제표로 전환된 환경에서 연간 이익 공시 시즌의 주가표류현상의 특성에 대한 분석을 수행하였다. 국제회계기준 도입 이후 연결재무제표와 별도재무제표가 동시에 공시되면서 두 가지 재무제표가 담고 있는 정보가 크게 차이가 있을 경우 개별재무제표가 주재무제표인 환경에 익숙한 국내 투자자들에게는 오히려 혼란을 초래할 수도 있다. 즉, 연결-별도 이익의 차이가 큰 경우 투자자들은 이 차이에 담긴 의미를 명확하게 파악할 수 있을 때까지 의사결정을 미룰 것이며, 이로 인해 주가표류현상이 더 크게 나타날 수 있다. 구체적으로 본 연구는 2012년부터 2014년까지 유가증권시장에 상장된 12월 결산 비금융업에 속한 1,446 기업-연도 표본을 이용하여 실증분석을 수행하였다. 연결재무제표와 별도재무제표상에 표시된 이익의 차이는 비기대이익의 차이와 주당순이익의 차이로 측정하였으며 각각의 중위수를 기준으로 그룹을 구분하였다. 분석 결과 비기대이익의 차이가 큰 집단이 작은 집단보다 주가표류현상이 더 큰 것으로 나타났다. 연결주당순이익과 별도주당순이익의 차이를 기준으로 구분한 결과도 이와 동일하게 나타났다. 본 연구의 분석 결과를 종합하면 연간이익 공시시점(주주총회소집공지일) 이후에 상당기간 동안 주가표류현상이 존재하며, 이러한 표류현상은 공시되는 두 가지 이익, 즉 연결이익과 별도이익의 차이가 클수록 더 크다는 것이다. 이는 두 가지 이익의 차이가 클수록 추가정보를 확인하는 과정으로 인하여 지연반응이 더 강하게 나타나고 있다는 해석이 가능하다. 본 연구의 결과는 국제회계기준 도입 이후 변화된 환경으로 인한 연간이익 공시시즌의 시장의 지연반응과 관련한 추가적인 해석을 제시했다는 점에서 의의를 찾을 수 있다. 본 연구의 결과는 자본시장을 감독하는 감독당국은 물론이고 공시 정보를 생산하는 기업, 그리고 정보이용자들에게 중요한 시사점을 제공할 것으로 기대된다.

연구논문 : K-IFRS 도입에 따른 이익공시후 주가표류현상의 특성에 대한 분석: 연결재무제표이익과 별도재무제표이익의 차이를 중심으로

박석진(제1저자) ( Suk Jin Park ),이은철(교신저자) ( Eun Chul Lee ) 한국회계학회 2015 회계저널 Vol.24 No.6

본 연구는 2011년 국제회계기준 도입 이후 연결재무제표가 주재무제표로 전환된 환경에서 연간 이익 공시 시즌의 주가표류현상의 특성에 대한 분석을 수행하였다. 국제회계기준 도입 이후 연결재무제표와 별도재무제표가 동시에 공시되면서 두 가지 재무제표가 담고 있는 정보가 크게 차이가 있을 경우 개별재무제표가 주재무제표인 환경에 익숙한 국내투자자들에게는 오히려 혼란을 초래할 수도 있다. 즉, 연결-별도 이익의 차이가 큰 경우 투자자들은 이 차이에 담긴 의미를 명확하게 파악할 수 있을 때까지 의사결정을 미룰 것이며,이로 인해 주가표류현상이 더 크게 나타날 수 있다. 구체적으로 본 연구는 2012년부터 2014년까지 유가증권시장에 상장된 12월 결산 비금융업에 속한 1,446 기업-연도 표본을 이용하여 실증분석을 수행하였다. 연결재무제표와 별도재무제표상에 표시된 이익의 차이는 비기대이익의 차이와 주당순이익의 차이로 측정하였으며 각각의 중위수를 기준으로 그룹을 구분하였다. 분석 결과 비기대이익의 차이가 큰 집단이 작은 집단보다 주가표류현상이 더 큰 것으로 나타났다. 연결주당순이익과 별도주당순이익의 차이를 기준으로 구분한 결과도 이와 동일하게 나타났다. 본 연구의 분석 결과를 종합하면 연간이익 공시시점(주주총회소집공지일) 이후에 상당기간동안 주가표류현상이 존재하며, 이러한 표류현상은 공시되는 두 가지 이익, 즉 연결이익과별도이익의 차이가 클수록 더 크다는 것이다. 이는 두 가지 이익의 차이가 클수록 추가정보를 확인하는 과정으로 인하여 지연반응이 더 강하게 나타나고 있다는 해석이 가능하다. 본 연구의 결과는 국제회계기준 도입 이후 변화된 환경으로 인한 연간이익 공시시즌의 시장의 지연반응과 관련한 추가적인 해석을 제시했다는 점에서 의의를 찾을 수 있다. 본 연구의 결과는 자본시장을 감독하는 감독당국은 물론이고 공시 정보를 생산하는 기업, 그리고 정보이용자들에게 중요한 시사점을 제공할 것으로 기대된다. Korea made International Financial Reporting Standards(IFRS) application mandatory for all listed companies in Korea effective from 2011. Under IFRS, according to whether entities have subsidiaries or not, they prepare three types of financial statements. One is individual financial statements, another is consolidated financial statements, and the other is separate financial statements. As for the controlling entities that prepare consolidated financial statements, they are required to prepare separate financial statements together with the consolidated financial statements in accordance with IFRS. While consolidated financial statements present the financial position and operating results for a parent company and its subsidiaries as if they were a single economic entity, separate financial statements are financial statements prepared by a parent, or an investor in a joint venture etc., where those investments are accounted for either at cost or fair value. Before IFRS adoption, individual financial statements are primary financial statements in Korea. Under IFRS, an entity that does not have a subsidiary prepares individual financial statements. However, as for the entities having one or more subsidiaries, consolidated financial statements are prepared as primary financial statements and separate financial statements are treated as supplementary financial statements under IFRS regime. Unlike separate financial statements, individual financial statements are financial statements that investments in associates are required to be accounted for using the equity method. Investors who familiar with individual financial statements might be confused with the information contents disclosed in separate financial statements and consolidated financial statements. Especially the difference between separate and consolidated earnings may cause confusion in making decisions by information users. This confusion can be explained by the hypothesis of functional fixation. Functional fixation hypothesis is that individual investors interpret earnings numbers the same way regardless of the accounting procedure used to calculate them, so there would be mechanical relation between earnings and stock prices(Watts and Zimmerman 1986). According to Watts and Zimmerman``s interpretation, the functional fixation hypothesis is that investors do not discriminate between earnings calculated using different procedures because it is costly to adjust the numbers or investors are irrational. This study examines whether the difference between separate and consolidated earnings is associated with post earnings announcement drift(PEAD). PEAD is the tendency for stock``s cumulative abnormal returns to drift in the direction of the earnings surprise after earnings announcement. PEAD is considered as one of the market anomaly that is in a conflict with semi-strong efficient market hypothesis. This phenomenon was first discovered by Ball and Brown(1968). They reported that stock returns continue to drift in the direction of earnings surprise for several months after earnings announcements. If investors are confused with entity``s information, the stock price reaction to earnings announcements may not fully reflect the information contained in the earnings announcement. In this paper, We analyze 1,466 non-financial and December year-end firm/year observations listed in the KOSPI market. Sample period spans from 2012 to 2014. Our hypothesis is that the difference between separate and consolidated earnings is positively related with PEAD. The difference between separate and consolidated earnings is measured in two ways. One is the difference between separate and consolidated unexpected earnings, the other is the difference between separate and consolidated earnings per share. We find following empirical results. The level of PEAD and the difference between separate and consolidated earnings has positive relation. This result implicates that consolidated financial statements and separate financialstatements with different information contents may cause confusion in investment decision making by users of accounting information. This paper contributes to the literature by examining the difference between separate and consolidated earnings on PEAD under IFRS regime. Overall, our results suggest that the inefficiency of the market exists in Korea due to confusion with the different information contents in separate and consolidated financial statements. These findings provide valuable insights to investors and other interested users who need to use consolidated financial statementsand separate financial statements for their investment decision making.

악간고정과 교합 상이 호흡기능에 미치는 영향에 관한 실험적 연구

이중규(Joong-Kyou Lee),김경욱(Kyung-Wook Kim),이재훈(Jae-Hoon Lee) 대한구강악안면외과학회 2002 대한구강악안면외과학회지 Vol.28 No.3

Intermaxillary fixation and occusal splint are routine procedure for maxillofacial fracture and orthognathic surgery. When these methods could obstruct oral airway the patients who kept intermaxillary fixation and occusal splint in their mouth, are very difficult to breath after surgery. Nasal bleeding and pharyngeal edema due to nasotracheal intubation, residual effect of muscle relaxants, and anesthetic agent could be contributing factor of airway obstruction. In this study, pulmonary function test was evaluated before and after intermaxillary fixation, and intermaxillary fixation with occusal splint in 22 volunteers. The results were as follows 1. FVC, %FVC, FEV1, FEV1%, PEF, PEF50, MVV without intermaxillary fixtion were 4.45L, 88%, 4.03L, 90.9%, 10.26L/s, 5.53L/s, and 136.14L/min, and with intermaxillary fixation were 3.51L, 68.67%, 3.06L, 69.39L, 6.52L/s, 3.94L/s, and 69.39L/min. The results with intermaxillary fixation and occusal splint were 2.15L, 42.41%, 1.71L, 38.81%, 2.83L/s, 1.74L/s, and 37.14L/min. 2. Compared with before and after intermaxillary fixation, all values of pulmonary function test were decreased and after intermaxillary fixation and intermaixillary fixation with occulasal splint, the results were decreased. 3. MVV and PEF were decreased significantly with interaxillary fixtion and occusal splint, and FVC was less decreased. It meant that intermaxillary fixation and occluasal splint induced reduction of respiratory flow significantly, but less reduction of respiratory volume. 4. Intermaxillary fixation and occulsal splint induced increase of airway resistance, decrease of expiratory volume and air flow. So severe respiratory difficulty could be seen to all volunteers who kept intermaxillary fixtion and occusal splint. 5. In classification of respiratory difficulty, intermaxillary fixation with occulsal splint induced complex respiratory difficulty more than intermaxillary fixation only did. From the above results, doctors who care patients kept intermaxillary fixation and occusal splint should be aware of respiratory depression caused by these treatment.

비상위험준비금의 경제적 실질과 한국자본시장의 기능고착현상에 관한 연구

조석희 ( Seok Hee Cho ) 한국보험학회 2017 保險學會誌 Vol.109 No.-

본 논문에서는 한국의 손해보험회사들이 재무제표에 공시하고 있는 비상위험준비금의 경제적 실질과 이와 관련하여 나타나는 한국 자본시장의 기능고착현상을 연구하였다. 이를 위해서 본 논문은 비상위험준비금의 경제적 실질과 기능고착현 상에 대한 일정한 가정을 도입하고 한국의 IFRS 도입에 따른 비상위험준비금의 가치관련성 변화를 분석하였다. 분석결과, IFRS 도입 이전에는 비상위험준비금의 가치관련성이 유의하지 않게 나타났으나, IFRS 도입 이후에는 정 (+)의 가치관련성을 가지는 것으로 관찰되었다. 이러한 변화가 경제적 실질의 변화 없는 재무제표 표시방법 변화와 함께 나타 났다는 사실은 한국의 자본시장에 기능고착현상이 존재한다는 증거를 제공한다. 그리고 기능고착현상의 발생요건과 그 작동방향을 고려할 때 동 준비금의 경제적 실질은 기업가치에 긍정적인 요소로 추정되었다. 비상위험준비금의 경제적 실질과 시장의 평가결과(가치관련성)를 동일시하거나 기능고착현상의 존재 가능성만을 언급한 선행연구와는 달리,비상위험준비금과 관련된 몇 가지 속성들 사이의 관계를 이용하여 기능고착현상을 체계적으로 분석한 점은 이 논문의 차별화된 공헌점이다 This paper examined the economic substance of catastrophe reserve which Korean non-life insurance companies disclose in their financial statements and functional fixation embedded in Korean capital market. To accomplish the purpose of this paper, some assumption about the economic substance of catastrophe reserve and functional fixation was adopted and the difference of catastrophe reserve`s value relevance according to the IFRS adoption was analysed. The results of this study are as follow. Before the IFRS adoption, the value relevance of catastrophe reserve was not significant, after the IFRS adoption, however, the catastrophe reserve had a positive value relevance. This result that there is a market evaluation change according to the change the way catastrophe is presented in their financial statements without the changes in economic substance is the evidence showing that there is a functional fixation in the Korean capital market. Considering the condition that occurs functional fixation and the directionality of them, the economic substance of catastrophe reserve was able to be interpreted as a positive factor for firm`s value. This paper analyzed the functional fixation under the relation among several properties of catastrophe reserve using the systematic research model, differentiating from prior researches that simply presented a possibility in being of functional fixation or equated the observed property (value relevance) with the catastrophe reserve`s economic substance.

악간고정이 호흡기능에 미치는 영향에 대한 임상적 연구

김철환,김미숙,Kim, Chul-Hwan,Kim, Mi-Suk 대한구강악안면외과학회 1999 대한구강악안면외과학회지 Vol.25 No.4

Intermaxillary fixation is routine procedure to oral and maxillofacial area in jaw bone fracture, surgical correction of jaw deformity, osseus reconstruction of jaw. After transoral surgery, accompanied by intermaxillary fixation, dysphagia or airway obstruction may be followed due to blood clot, vomitus, or laryngeal spasm resulting from irritation by blood or secretions. Lingual or pharyngeal edema is other contributing factors of airway obstruction. In addition, intermaxillary fixation itself may cause obstruction of airway. In this study, pulmonary function test and arterial blood gas analysis were evaluated before and after intermaxillary fixation in 30 patients suffered from mandibular fractures. Comparative analysis was performed by estimated values. The results were as followed. 1. The spirometric values of FEV1, FEV1/FVC and FEF25-75% without intermaxillary fixation were reduced from 97.57%, 85.1%, 98.3,% to 71.7%, 66.5%, 61.2% with intermaxillary fixation, indicating the presence of obstructive pulmonary impairment. 2. Spirometric value of MVV, as the most influencing value of sensitive to extrapulmonary factors, was changed from 84.5% to 46.48%. 3. After intermaxillary fixation, the spirometric value of FVC, as indicator of restrictive pattern of pulmonary function, was not reduced significantly as measured from 94.47% to 89.97%. 4. $O_2$ saturation of arterial blood gas analysis without intermaxillary fixation was 97.86%. While intermaxillary fixation, $O_2$ saturation was 97.47%. The results indicate that careful airway management is mandatory undergoing intermaxillary fixation of various oral and maxillofacial surgery.

AO 분류 C형 원위 요골 골절 환자에서 외고정술과 내고정술의 치료 결과의 비교

이윤민 ( Yoon-min Lee ),이화성 ( Hwa-sung Lee ),송석환 ( Seok-whan Song ),최재훈 ( Jae-hoon Choi ),박종태 ( Jong-tae Park ) 대한골절학회 2018 대한골절학회지 Vol.31 No.3

목적: AO 분류 C형 원위 요골 골절에서 금속판을 이용한 내고정술과 외고정술로 치료 결과를 비교하여 소분류에 따른 치료 방법을 제시하고자 하였다. 대상 및 방법: AO C형 원위 요골 골절 환자에서 금속판을 사용한 1군(85예)과 외고정기를 사용한 2군(116예)으로 구분하여 관절 운동 범위와 Green and O’Brien score로 임상 경과를 평가하였고 방사선적 결과를 분석하였다. 결과: 수술 12개월 추시 시 1군은 굴곡 64.4°, 신전 68.3°, 척측굴 30.6°, 요측굴 20.8°, 회외전 76.1°, 회내전 79.4°였고 2군은 굴곡 60.5°, 신전 66.9°, 척측굴 25.5°, 요측굴 18.6°, 회외전 73.5°, 회내전 75.0°였다. Green and O’Brien score 는 1군이 92.2점, 2군이 88.6점이었다. 1군/2군의 요골 높이 11.6/11.4 mm, 요골 경사 23.2°/22.5°, 전방 경사는 11.6°/8.7°, 척골 변위 1.27/0.93 mm였다. 결론: 본 연구와 같이 적절한 수술 술기와 수술 후 관리가 이루어진 외고정술은 금속판을 이용한 내고정과 유사한 임상결과를 얻을 수 있었다. Purpose: The purpose of this study was to evaluate the radiological and clinical results of plate fixation and external fixation with additional devices for treating distal radius fracture in AO type C subtypes, and propose a treatment method according to the subtypes. Materials and Methods: Two hundred and one AO type C distal radius fracture patients were retrospectively reviewed. Eighty-five patients in group 1 were treated with volar or dorsal plate, and 116 patients in group 2, were treated with external fixation with additional fixation devices. Clinical (range of mtion, Green and O’Brien’s score) and radiological outcomes were evaluated. Results: At the 12-month follow-up, group 1 showed flexion of 64.4^o, extension of 68.3^o, ulnar deviation of 30.6^o, radial deviation of 20.8^o, supination of 76.1^o, and pronation of 79.4^o in average; group 2 showed flexion of 60.5^o, extension of 66.9^o, ulnar deviation of 25.5^o, radial deviation of 18.6^o, supination of 73.5^o, and pronation of 75.0^o in average. The mean Green and O’Brien score was 92.2 in group 1 and 88.6 in group 2. The radial height of group 1 and group 2 was 11.6/11.4 mm; radial inclination was 23.2^o/ 22.5^o; volar tilt was 11.6^o/ 8.7^o; and the ulnar displacement was 1.27/0.93 mm. Conclusion: Judicious surgical techniques during device application and tips for postoperative management during external fixation can produce similar clinical results compared with internal fixation patients.

상완골 원위부 골절에 대한 내고정 후 주관절의 기능과 합병증

안혁수 ( Hyug Soo Ahn ),조영호 ( Young Ho Cho ),변영수 ( Young Soo Byun ),권도엽 ( Do Yop Kwon ),남승오 ( Seung Oh Nam ),김동영 ( Dong Young Kim ) 대한골절학회 2006 대한골절학회지 Vol.19 No.1

목적: 상완골 원위부 골절에 대하여 내고정을 시행하고 주관절의 기능과 합병증을 분석하였다. 대상 및 방법: 상완골 원위부 골절 38예를 대상으로 하였으며, AO 분류에 따른 골절의 형태는 A형이 12예, B형이 7예, C형이 19예였다. A형과 C형 골절 중 하 골주 골절이 각각 6예와 9예였으며, 개방성 골절이 C형에서 6예가 있었다. 골유합의 시기와 합병증을 조사하였고, Jupiter 등의 방법에 따라 주관절의 기능을 평가하였다. 결과: 평균 골유합 기간은 A형은 10.6주, B형은 7.7주, C형은 11.5주였다. 합병증으로 척골신경의 부분 마비가 6예, 고정 상실이 2예, 금속판 파손으로 인한 불유합이 1예, 이소성 골화가 1예, 외상성 관절염이 1예 발생하였다. 주관절의 기능은 34예 (89%)에서 우수 또는 양호의 결과를, 4예 (11%)에서 보통 또는 불량의 결과를 보였다. 개방성 골절이 폐쇄성 골절보다 결과가 좋지 못하였으며 나이, 성별, 손상 기전 및 골절의 형태에 따른 차이는 없었다. 결론: 대부분의 상완골 원위부 골절에서 만족스러운 결과를 얻기 위해서는 견고한 고정과 조기 운동이 요구되며, 술 후 합병증으로 척골신경의 부분 마비가 많이 발생하고 개방성 골절이 폐쇄성 골절보다 결과가 좋지 못하므로 주의를 요한다. Purpose: To evaluate the functional results of the elbow and the complications after internal fixation for distal humeral fractures. Materials and Methods: We reviewed 38 distal humeral fractures; 12 type A, 7 type B and 19 type C by AO classification. There were six low columnar fractures in type A and nine in type C. Six type C fractures were open. The fracture healing and complications were assessed and the functional result was evaluated by rating system of Jupiter et al. Results: Type A fractures were healed in an average of 10.6 weeks, type B 7.7 weeks and type C 11.5 weeks. Ulnar neuropathy occurred in six cases, loss of fixation in two cases, nonunion in one case, heterotopic ossification in one case and traumatic arthritis in one case. The functional result showed excellent or good in 34 cases (89%) and fair or poor in 4 cases (11%). Open fractures showed significantly worse result than closed fractures. Conclusion: To obtain the satisfactory results, stable fixation followed by early motion is required in most distal humeral fractures. Ulnar neuropathy occurs postoperatively in high incidence and the result of open fractures is worse than that of closed fractures.

Novel mono-and bi-functional phosphonium salts deriving from toxic phosphine off-gas as efficient catalysts for chemical fixation of CO2

Ju-Ping Dong,Chen Zhao,Jin-Jun Qiu,Cheng-Mei Liu 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.90 No.-

Utilizing phosphine (PH3) tail gas as starting feedstock, a series of novel mono-and bifucntionalphosphonium compounds (P+(CH2CH2CN)3RX , X= Br, I) was prepaed by a sustainable preparation route. The newly prepared phosphonium halides show high thermal stability and their degradationtemperature are far higher than that of CO2 chemicalfixation. The mono-fucntional phosphoniumsalts combinate with ZnBr2 to form an efficient Lewis acid/base type catalytic system for CO2 chemicalfixation and the bifucntional phosphonium salts alone shows same catalytic effects. The effects oftemperature, CO2 pressure, composition of the catalytic system on coupling reaction of CO2 withepoxides are investigated to evaluate the catalytic performance. The results illustrate that 96.7% cyclicCarbonate yield can be obtained in presence of ZnBr2/P+(CH2CH2CN)3C4H9Br (molar ratio = 1:10) under120 C, 1.5MPa of CO2 pressure in solvent-free condition, menawhile bifuntional phiospohonium salt Br-P+(CH2CH2CN)3C2H4COOH alone shows better catalytic perofromance.

A Density Functional Study of Amine Catalysts for CO2 Fixation into Cyclic Carbonates

류설 대한화학회 2019 Bulletin of the Korean Chemical Society Vol.40 No.10

The catalytic efficiency of three different kinds of amine groups for a prototype reaction of propylene oxide and carbon dioxide was investigated using density functional and energetic span model calculation. Our study demonstrated that tertiary amine groups perform best as catalyst at 100?°C and 10 bars because the corresponding catalytic cycle is free of any proton to be transferred around different molecular fragments. With primary or secondary amine catalysts, however, one or two protons at the nitrogen atom of amine can be transferred to the oxide oxygen, leading to intermediate structures stabilized by intramolecular hydrogen bonding at a deep valley in catalytic cycle. It is concluded that, when compared with the cases of primary or secondary amine groups, the effectiveness of tertiary amine group in catalysis originates from least hindrance to final products in catalytic cycle due to the absence of protons transferred.

Type I Chiari Malformation Without Concomitant Bony Instability: Assessment of Different Surgical Procedures and Outcomes in 73 Patients

Kamlesh Rangari,Kuntal Kanti Das,Suyash Singh,Krishna G. Kumar,Kamlesh Singh Bhaisora,Jayesh Sardhara,Anant Mehrotra,Arun Kumar Srivastava,Awadhesh Kumar Jaiswal,Sanjay Behari 대한척추신경외과학회 2021 Neurospine Vol.18 No.1

Objective: Posterior fossa decompression is the treatment of choice in type 1 Chiari malformation (CM-1) without bony instability. Although surgical fixation has been recommended by a few authors recently, comparative studies to evaluate these treatment strategies using objective outcome tools are lacking. Methods: Seventy-three patients with pure CM-1 (posterior fossa bony decompression [PFBD], n=21; posterior fossa bony and dural decompression [PFBDD], n=40; and posterior fixation [PF], n=12) underwent a postoperative outcome assessment using Chicago Chiari Outcome Score (CCOS). Logistic regression analysis detected predictors of an unfavorable outcome. Results: Minimally symptomatic patients generally underwent a PFBD while most of the clinically severe patients underwent a PFBDD (p=0.049). The mean CCOS score at discharge was highest in the PF (12.0±1.41) and lowest in PFBDD group (10.98±1.73, p=0.087). Patients with minimal preoperative clinical disease severity (adjusted odds ratio [AOR], 4.58; 95% confidence interval [CI], 1.29–16.31) and PFBDD (AOR, 7.56; 95% CI, 1.70–33.68) represented risks for an unfavorable short-term postoperative outcome. Though long-term outcomes (CCOS) did not differ among the 3 groups (p=0.615), PFBD group showed the best long-term improvements (mean follow-up CCOS, 13.71±0.95), PFBDD group improved to a comparable degree despite a poorer short-term outcome while PF had the lowest scores. Late deteriorations (n=3, 4.1%) occurred in the PFBDD group. Conclusion: Minimally symptomatic patients and PFBDD predict a poor short-term postoperative outcome. PFBD appears to be a durable procedure while PFBDD group is marred by complications and late deteriorations. PF does not provide any better results than posterior fossa decompression alone in the long run.