생산성 충격이 실질 환율과 순수출에 미치는 영향의 국별 비교

학위논문 (박사) -- 서울대학교 대학원 : 사회과학대학 경제학부, 2021. 2. 김소영.생산성 증가 충격이 실질 환율에 미치는 영향에 대한 연구는 다양하게 이루어졌다. 그러나 그간의 연구는 이론 연구의 비중이 높고, 실증 분석은 미국을 대표로 하는 대규모 경제에서의 생산성 증가가 전세계 경제에 미치는 영향으로 한정되어 있다. 또한 이론 연구에서는 모델 별로 환율의 변화방향을 다르게 예측하고 있어 연구 결과에 일관성이 결여되어 있다. 이 논문은 다수의 국가 샘플을 이용해 생산성 충격의 파급효과를 분석하고, 국가의 특성에 따라 영향이 달라질 수 있다는 결과를 제시한다. 또한 소규모 개방경제에서 생산성 충격이 발생했을 때 환율과 순수출의 변화를 분석하고, 미국의 결과와 비교한다. 첫째, 기존 연구가 미국의 생산성 증가가 전세계 경제에 미치는 영향을 분석한데 반해, 이 논문은 미국의 생산성 충격이 48개 개별 국가에 미치는 영향을 분석한다. 미국의 생산성 충격은 VAR(Vector Autoregressive) 모델에서 변수에sign restriction을 적용해 식별하고, 국가별 영향의 차이가 발생하는 원인은 cross-country OLS(Ordinary Least Square)를 이용해 분석한다. 분석 결과 전체적인 미국의 실질 환율은 절상하고 순수출은 감소하지만, 개별 국가에서는 미국의 실질 환율이 절상과 절하가 모두 존재하고 순수출도 감소와 증가가 모두 관찰된다. 실질 환율의 경우, 소비에서 자국 제품 선호도가 높고 미국과 강한 무역 관계를 가지거나 무역 개방도가 높은 국가에서 미국의 실질 환율이 절상하는 것으로 분석됐다. 무역의 경우, 미국의 실질 환율이 절상한 국가로는 미국의 수출이 감소하고, 미국은 생산성 증가 이후 중간재 수입을 늘리는 것으로 나타났다. 전체적인 미국의 수출은 감소하지만, 금융시장이 발전한 국가로의 수출은 오히려 증가하는 것으로 분석됐다. 둘째, 기존 연구는 대규모 경제에서 생산성 충격을 분석했지만, 이 연구는 소규모 개방경제에서 생산성 충격이 발생할 경우 그 국가의 실질 환율과 순수출의 반응을 분석하였다. 소규모 개방경제 샘플은 일본, 남아프리카 공화국, 캐나다. 프랑스, 노르웨이, 핀란드, 독일, 아일랜드, 호주, 영국의10개 국가로 구성된다. 미국에서는 생산성이 증가했을 때 실질 환율이 절상하고 순수출이 감소했지만, 소규모 개방경제에서는 미국과 반대방향으로 변수가 반응하는 경우가 나타났다. 미국의 경우처럼 생산성 증가 이후 실질 환율이 절상하는 국가에서는 공통된 특징이 발견되었다. 생산성 증가 이후 자산 효과가 크고 소비에서 자국 제품을 선호하는 경향이 높은 국가에서는 실질 환율이 미국의 경우처럼 절상하였다.International transmission of productivity shock, specifically the effects on the real exchange rate (RER), is a widely discussed issue, but a large share of the literature consists of theoretical modeling, and the predictions of the models are inconsistent. Empirical studies are limited to shocks in large economies, mainly the US, and the aggregate impact on the global economy is tested. In other words, previous studies investigate how the world economy as a whole is affected by productivity growth in large economies. This thesis, however, investigates the effects of US productivity shocks on 48 individual countries and finds that the responses can differ, depending on country characteristics. In addition, productivity shocks in small open economies are investigated and the responses are compared to the results found in a large economy, the US. First, this study investigates the effects of US productivity shock on 48 countries. US productivity shock is identified via sign restrictions in the Vector Autoregressive (VAR) model and the influence of country characteristics on the effects is tested with cross-country Ordinary Least Square (OLS). This study finds novel evidence that aggregate US RER appreciates but bilateral RER can appreciate or depreciate, depending on country characteristics. A country experiences appreciation in US RER if it has high consumption home bias, a strong trade relationship with the US, or its economy is more open to trade. Aggregate US net exports decline because of decreased exports and increased imports. In terms of bilateral trade, US exports to countries where the US RER appreciates more decline, and imports of intermediate goods to the US increases. US net exports increase to countries where the financial markets are more complete. Second, this study investigates productivity shocks in 10 small open economies and documents the responses of aggregate RER and net exports. The 10 countries are Japan, South Africa, Canada, France, Norway, Finland, Germany, Ireland, Australia, and the UK. While the RER appreciates and net exports decrease in the US after productivity growth, there are varied responses in small open economies. An appreciation in the RER, similar to the effect in the US, is witnessed in a group of countries where strong wealth effect occurs and there is a high consumption home bias.Abstract II Chapter 1 1 Introduction 1 Chapter 2. Productivity Shock in the US and Its Effects on 48 Countries 8 2.1 Introduction 8 2.2 Productivity Shock and Its Impact 11 2.3 Different Impact Across Countries and the Role of Country Characteristics 27 2.4 Robustness 46 2.5 Conclusion 52 Chapter 3. Productivity Shocks in Small Open Economies and International Transmission 54 3.1 Introduction 54 3.2 Structural VAR with Sign Restrictions 56 3.3 Empirical results 60 3.4 Robustness 67 3.5 Comparison to the US 69 3.6 Conclusion 76 Chapter 4. Conclusion and Discussion 78 References 82 국문초록 87Docto

간문맥에서 생긴 미만성 거대 B세포 림프종

Tumor thrombus in the portal vein without any liver parenchymal abnormality is extremely rare. In the liver, the primary tumor most frequently presenting with intravascular tumor thrombi is hepatocellular carcinoma and lymphoma is rarely considered. Even though thrombosis occurs quite often in lymphoma, cases of tumor thrombus are rare and cases of tumor thrombus in the portal vein are even rarer. Only four cases of lymphoma with portal vein tumor thrombosis have been reported to date and all cases were the result of direct extensions of a dominant nodal or extra-nodal mass. To our knowledge, there has been no report on diffuse large B-cell lymphoma (DLBCL) presenting only within the lumen of the portal vein and not intravascular B-cell lymphoma. We present the first case of DLBCL presenting only within the lumen of the portal vein in an immunocompetent patient.ope

Noninvasive Biomarker for Predicting Treatment Response to Concurrent Chemoradiotherapy in Patients with Hepatocellular Carcinoma

Purpose: To investigate noninvasive biomarkers for predicting treatment response in patients with locally advanced HCC who underwent concurrent chemoradiotherapy (CCRTx). Materials and Methods: Thirty patients (55.5 ± 10.2 years old, M:F = 24:6) who underwent CCRTx due to advanced HCC were enrolled. Contrast-enhanced US (CEUS) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) were obtained before and immediately after CCRTx. The third CEUS was obtained at one month after CCRTx was completed. Response was assessed at three months after CCRTx based on RECIST 1.1. Quantitative imaging biomarkers measured with CEUS and MRI were compared between groups. A cutoff value was calculated with ROC analysis. Overall survival (OS) was compared by the Breslow method. Results: Twenty-five patients were categorized into the non-progression group and five patients were categorized into the progression group. Peak enhancement of the first CEUS before CCRTx (PE1) was significantly lower in the non-progression group (median, 18.6%; IQR, 20.9%) than that in the progression group (median, 59.1%; IQR, 13.5%; P = 0.002). There was no significant difference in other quantitative biomarkers between the two groups. On ROC analysis, with a cutoff value of 42.6% in PE1, the non-progression group was diagnosed with a sensitivity of 90.9% and a specificity of 100%. OS was also significantly longer in patients with PE1 < 42.6% (P = 0.014). Conclusion: Early treatment response and OS could be predicted by PE on CEUS before CCRTx in patients with HCC.ope

췌장 선암의 절제 가능성 평가

Imaging studies play an important role in the detection, diagnosis, assessment of resectability, staging, and determination of patient-tailored treatment options for pancreatic adenocarcinoma. Recently, for patients diagnosed with borderline resectable or locally advanced pancreatic cancers, it is recommended to consider curative-intent surgery following neoadjuvant or palliative therapy, if possible. This review covers how to interpret imaging tests and what to consider when assessing resectability, diagnosing distant metastasis, and re-assessing the resectability of pancreatic cancer after neoadjuvant or palliative therapy.ope

MRI Findings and Prediction of Time to Progression of Patients with Hepatocellular Carcinoma Treated with Drug-eluting Bead Transcatheter Arterial Chemoembolization

The purpose of this study was to investigate the utility of MRI findings after drug-eluting beads (DEB) - transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma in predicting time to progression (TTP). This study included 48 patients with 60 lesions who underwent liver MRI within 3 months after DEB-TACE. MRI was assessed for arterial enhancement pattern, late washout, arterioportal shunt, signal intensity on T2-weighted image, intratumoral septa, enhancing tissue on subtraction images, and treatment response. Cox-regression analysis was performed to identify independent factors to predict TTP. TTP was calculated using the Kaplan-Meier method with the log-rank test. Per lesion, 30 achieved complete remission, 22 had a partial response, and the remaining 8 lesions displayed stable disease on MRI. Arterial enhancement pattern, washout and enhancing tissue on subtraction images from MRI were associated with viable tumor on the last follow-up computerized tomography. Arterial enhancement, washout and enhancing tissue on subtraction images were significant predictors of TTP, but only enhancing tissue on subtraction images remained a significant predictor of TTP (P=0.018) in the multivariate analysis. TTP was longer in the group without enhancing tissue on subtraction images compared to the group with enhancing tissue (601 days vs. 287 days, P<0.001). Enhancing tissue on subtraction images from MRI after DEB-TACE is predictive for longer TTP.ope

Contrast-enhanced US with Perfluorobutane(Sonazoid) used as a surveillance test for Hepatocellular Carcinoma (HCC) in Cirrhosis (SCAN): an exploratory cross-sectional study for a diagnostic trial

Background: Ultrasonography (US) is widely used as a standard surveillance tool for patients who are at a high risk of having hepatocellular carcinoma (HCC); however, conventional B-mode US appears to be insufficient in order to ensure the early detection of HCC. Perfluorobutane allows very stable Kupffer phase imaging for at least 60 min, which is tolerable for examinations of the entire liver. The purpose of our study is to evaluate the added value of contrast-enhanced US using perfluorobutane to that of conventional B-mode US as an HCC surveillance tool for patients with liver cirrhosis. Methods/design: SCAN (Sonazoid-US for surveillance of hepatoCellulArcarciNoma) is a prospective, multi-institutional, diagnostic trial using an intra-individual comparison design in a single arm of patients. This study was approved by our five institutional review board and informed consent was obtained from all participating. We obtained consent for publication of these data (contrast enhanced US images, CT or MRI images, laboratory findings, age, sex) from all participating patients. All patients will undergo conventional B-mode US immediately followed by contrast-enhanced US. The standardized case report forms will be completed by operating radiologists after B-mode US and contrast-enhanced US, respectively. If any lesion(s) is detected, the likelihood of HCC will be recorded. The primary endpoints are a detection rate of early-stage HCC and a false referral rate of HCC. Intra-individual comparison using Mcnemar's test will be performed between B-mode US and contrast-enhanced US. The study will include 523 patients under HCC surveillance in five medical institutions in Korea. Discussion: SCAN is the first study to investigate the efficacy of contrast-enhanced US in surveillance using two reciprocal endpoints specialized for the evaluation of a surveillance test. SCAN will provide evidence regarding whether patients can truly benefit from contrast-enhanced US in terms of the detection of early stage HCC while avoiding additional unnecessary examinations. In addition to the study protocol, we elaborate on potentially debatable components of SCAN, including the design of an intra-individual comparison study, study endpoints, composite reference standards, and indefinite imaging criteria regarding the likelihood of HCC. Trial registration: The date of trial registration (ClincalTrials.gov: NCT02188901 ) in this study is July 3, 2014. The last patient enrolled in August 30, 2016 and follow up to see the primary end point is still ongoing. All authors have no other relationships/conditions/circumstances that present a potential conflict of interest of relationships. Our study protocol has undergone peer-review by the funding body (GE Healthcare). No other relationships/conditions/circumstances that present a potential conflict of interest. Also, we clearly stated in the 'competing interests' section of my manuscript.ope

Essential Items for Structured Reporting of Rectal Cancer MRI: 2016 Consensus Recommendation from the Korean Society of Abdominal Radiology

High-resolution rectal MRI plays a crucial role in evaluating rectal cancer by providing multiple prognostic findings and imaging features that guide proper patient management. Quality reporting is critical for accurate effective communication of the information among multiple disciplines, for which a systematic structured approach is beneficial. Existing guides on reporting of rectal MRI are divergent on some issues, largely reflecting the differences in overall management of rectal cancer patients between the United States and Europe. The Korean Society of Abdominal Radiology (KSAR) study group for rectal cancer has developed an expert consensus recommendation regarding essential items for structured reporting of rectal cancer MRI using a modified Delphi method. This recommendation aims at presenting an up-to-date, evidence-based, practical, structured reporting template that can be readily adopted in daily clinical practice. In addition, a thorough explanation of the clinical and scientific rationale underlying the reporting items and their formats is provided. This KSAR recommendation may serve as a useful tool to help achieve more standardized optimal care for rectal cancer patients using rectal MRI.ope

담도선섬유종에서 발생한 담관암: 증례 보고 및 문헌적 고찰

Biliary adenofibromas are rare biliary epithelial tumors that are classified as benign. Nevertheless, some cases have been reported to show malignant transformations. The radiologic findings of biliary adenofibromas and their malignant transformation are not well-established because of their rarity. We present a case of a cholangiocarcinoma arising from a biliary adenofibroma assessed using ultrasonography, CT, and MRI. The differential diagnoses include other hepatic tumors.ope

The Use of Color Doppler Sonography to Avoid Misinterpretation of the Intrahepatic Portal Vein in Gray-Scale Sonographic Diagnosis of Cysts: Two Case Reports

The Use of Color Doppler Sonography Avoids Misinterpretation of the Intrahepatic Portal Vein in the Gray-Scale Sonographic Diagnosis of Cysts. When gray-scale US shows an intrahepatic cystic lesion with weak or no posterior acoustic enhancement in close proximity to the portal vein, especially at the bifurcation area, a detailed color Doppler US should be subsequently performed to evaluate its vascular nature.ope

Hepatobiliary phase signal intensity: A potential method of diagnosing HCC with atypical imaging features among LR-M observations

Herein, we assessed whether hepatobiliary phase (HBP) signal intensity (SI) can be used to differentiate HCC and non-HCC malignancies within LR-M observations. 106 LR-M patients based on LI-RADS v2018 who underwent gadoxetate-disodium magnetic resonance imaging and surgery from January 2009 to December 2018 were included. SI of LR-M observation on HBP was analyzed by two radiologists and categorized into dark, low and iso-to-high groups. Tumor was classified as dark when more than 50% of tumor showed hypointensity compared to spleen, as low when more than 50% of tumor showed hyperintensity compared to spleen but hypointensity compared to liver parenchyma, and as iso-to-high if there was even a focal iso-intensity or hyperintensity compared to liver parenchyma. Analysis of clinicopathological factors and association between imaging and histology was performed. Out of 106 LR-M, 42 (40%) were showed dark, 61 (58%) showed low, and 3 (3%) showed iso-to-high SI in HBP. Three iso-to-high SI LR-M were HCCs (P = 0.060) and their major histologic differentiation was Edmondson grade 1 (P = 0.001). 43 out of 61 (71%) low SI LR-M were iCCA or cHCC-CCA (P = 0.002). Inter-reader agreement of HBP SI classification was excellent, with a kappa coefficient of 0.872. LR-M with iso-to-high SI in HBP is prone to being HCC while LR-M with low SI in HBP is prone to being tumor with fibrous stroma such as iCCA and cHCC-CCA. Classification of LR-M based on HBP SI may be a helpful method of differentiating HCC from non-HCC malignancies.ope