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The expanded graphite has been used as a matrix to grow Ni2Co-LDH and this enabled to obtain stability and fast charging capabilities when used as anode for Li-ion batteries. The experimental findings are supported by DFT calculations.

In this study, we investigate important decisional factors for the purchase intention of animal welfare labeled beef in Korea considering direct and indirect paths (trust and attitudes). Using a structural equation model with 300 samples from the Korea consumer panel survey, we find that perceived knowledge and revealed information positively affect consumer purchase intention for beef labeled as supporting animal welfare. Our results also show that a subjective norm (positive opinions of friends or family on animal welfare) has a positive effect on the purchase of beef labeled as “welfare conscious.” Based on our results, we can derive policy implications for expanding animal welfare raising practices to achieve sustainable development in the livestock sector without ethical and environmental side effects. Three possible policy alternatives include an online word-of-mouth strategy for improving subjective norms, enhancing animal welfare labeling information, and setting up public education for such labeling.

Korea is not only a top paprika exporter to Japan, but also Japan is the largest Korean paprika importer. In this situation, investigating who has price leadership contributes to fill a gap in previous literature. This study examines paprika price relationships between wholesale prices in Korea, import prices in Japan and wholesale prices in Japan using monthly data from 2007 to 2017. A threshold vector autoregressive model (TVAR) and Granger causality test are used to test the price leadership between Korean exporters and Japanese importers. Moreover, forecasted prices based on TVAR show that Korean exporter’s paprika prices will be lower than Japanese importer’s price in the future. The results show that Japanese importers provide price leadership to wholesalers in Korea and Japan. Our findings suggest that paprika farmers could benefit from policies designed to address the trade situation.

NixFeyMoz layered double hydroxide (LDH) electrocatalysts fabricated via a simple hydrothermal technique for overall water splitting in an alkaline medium are reported.

The oxygen evolution reaction (OER) plays a key role in determining the performance of overall water splitting, while a core technological consideration is the development of cost-effective, efficient, and durable catalysts. Here, we demonstrate a robust reduced Fe-oxide@NiCo2O4 bilayered non-precious-metal oxide composite as a highly efficient OER catalyst in an alkaline medium. A bilayered oxide composite film with an interconnected nanoflake morphology (Fe2O3@NiCo2O4) is reduced in an aqueous NaBH4 solution, which results in a mosslike Fe3O4@NiCo2O4 (reduced Fe-oxide@NiCo2O4; rFNCO) nanostructured film with an enhanced electrochemical surface area. The rFNCO film demonstrates an outstanding OER activity with an extraordinary low overpotential of 189 mV at 10 mA cm–2 (246 mV at 100 mA cm–2) and a remarkably small Tafel slope of 32 mV dec–1. The film also shows excellent durability for more than 50 h of continuous operation, even at 100 mA cm–2. Furthermore, density functional theory calculations suggest that the unintentionally in situ doped Ni during the reduction reaction possibly improves the OER performance of the rFNCO catalyst shifting d-band centers of both Fe and Ni active sites.

This study investigates the causal relationship between total biomass energy consumption, total energy CO2 emissions, and GDP in the United States for the period January 1973–December 2016 by employing a directed acyclic graph (DAG) techniques and the Autoregressive Distributed Lag (ARDL) model. Additionally, this paper examines the existence of the environmental Kuznets curve (EKC) hypothesis. The result of the DAG reveals that total biomass energy consumption and GDP have a unidirectional contemporaneous causal relationship with total energy CO2 emissions. Based on the results of the ARDL, we find that a 1% increase in per capita total biomass energy consumption causes a 0.65% reduction in per capita total energy CO2 emissions in the long-run. This finding implies that expanding the usage of biomass is one way to reduce and control greenhouse gases in the US. Moreover, we find that the inverted U-shaped EKC hypothesis is satisfied for the US case. Findings from this study suggest that energy policies should stimulate an increase of biomass production for reducing total energy CO2.

This paper investigates the impact of new food safety regulations, a positive list system (PLS), on the vertical supply chain for bananas in Korea using monthly price data from January 2012 to Febr...

The oxygen evolution reaction (OER) plays a key role in determining the performance of overall water splitting, while a core technological consideration is the development of cost-effective, efficient, and durable catalysts. Here, we demonstrate a robust reduced Fe-oxide@NiCo

This paper investigates the impact of high U.S. maximum residue limit (MRL) standards on U.S vegetable exports to 102 countries utilizing the hierarchical model. MRL, which is one of non-tariff barriers with respect to food safety, is applied to home and foreign countries at the same time. Thus, firms in countries with higher food safety standards are expected to have a competitive advantage from the ‘signaling effect’. The results show that high MRL standards in the U.S. have a positive impact on U.S. vegetable exports, indicating the ‘signaling effect’ from the strict U.S. domestic MRL standards. The results provide policy makers with insights into how strict food safety regulations of the home country can be considered as a catalyst for increasing competitiveness in international markets.

This paper investigates the tourism-led growth hypothesis in the case of Korea considering a possible structural break from exogenous shocks, such as the Asian financial crisis in 1997 and the controlling policy of outbound travel in the latter half of the mid-1980s. To examine the possible structural break from exogenous shocks, we utilized a structural break unit root test. Adapting Granger causality test and variance decomposition, we found the relationship between tourism and economic growth in Korea. The results of the structural break test show that structural break points exist in 1979 and 1997 for tourism receipts and GDP, respectively. Before and after structural breaks points, we found a different relationship. We also found that a GDP shock only explained 22% of variation errors in tourism receipts based on the results of a variance decomposition. These results have contributions and implication to previous literature. First, the structural break from an exogenous shock can make a change in the relationship between tourism and economic growth. Second, a rise in GDP may lead to outbound tourism rather than domestic in Korea.

The historical decomposition and directed acyclic graph methods are employed to estimate the effect of avian influenza in Korea on egg price transmission between the farm, wholesale, and retail levels. Our findings suggest that farm and retail egg prices are connected by the wholesale price. We also find that the farm-wholesale and the wholesale-retail margins increase during the avian influenza period. Our results imply that the retailer and wholesaler use their market power to increase their price during the food safety crisis. Therefore, the Korean government should control market power by allowing more emergency egg imports.

This paper investigates what factors and characteristics of organic consumers affect annual organic food expenditure by using Nielsen&rsquo, s consumer panel dataset from 2010 to 2014. To be specific, this paper explores new marketing opportunities by investigating organic consumer heterogeneity in different household income levels by utilizing the multilevel model. Findings in this study will contribute to the previous and existing literature in three-folds. First, we find that the organic consumers are more heterogeneous in the high-level of income groups (approximately above $60,000), as well as the low-income households between $35,000 and $45,000. This finding demonstrates that the income levels above $60,000 and around $40,000 have potential market segmentation. Second, we find that that annual organic expenditure is positively associated with consumers who consecutively repurchase organic food products compared to irregular organic consumers, supporting a different level of satisfaction. Third, we find that USDA organic labeling has a positive effect on annual organic expenditure compared to the organic labeling certified by private companies, implying the importance of credibility for the organic labeling.

This study investigates price relationships between organic and conventional carrots, tomatoes, and lettuce in the U.S. utilizing Nielsen scanner data from 2006 to 2015. We employ a threshold vector error correction model (TVECM), threshold vector autoregressive model (TVAR), and threshold cointegration test to test whether market integration exists between organic and conventional vegetables as well as the existence of asymmetric price transmission. The results find positive long-run relationships between organic and conventional prices of carrots and tomatoes and show the existence of asymmetric price transmission in price pairs of lettuce and tomatoes. Our findings suggest that the price relationship between organic and conventional vegetables varies by characteristics, such as shelf life and volatility in the price premium. Furthermore, the results indicate that consumers in the U.S. recognize organic and conventional carrots and tomatoes as partially substitutable goods, while U.S. consumers consider organic and conventional lettuces as different goods (no cross-price relationship).

This paper examines the presence of habit formation effect and investigates the potential factors to derive new market implications for the U.S. organic food market by utilizing Nielsen’s consumer data from 2010 to 2014. Using a multilevel model analysis based on hierarch framework, this study finds the presence of habit formation, positive organic labeling effect, and possible market segmentation from different household income levels in the U.S. organic food market. Findings from this study contribute to previous literature related to organic food expenditures. It also supports grocery stores and certification companies to consider new market strategies in organic food market.

This paper examines the effects of aging and income subsidies on farm efficiency in Korea by utilizing the Korean Farm Household Economic Survey from 2008 to 2015. A stochastic frontier model with a non-monotonic assumption on the effect of efficiency factors is implemented to reflect a super aging and less developed production structure in Korean agriculture. This study finds continuously decreasing farm efficiency with age, which contradicts the commonly assumed inverted-U relationship between age and productivity. Especially, we find that labor is the most important factor to explain recent farm efficiency losses in Korea. Furthermore, this paper finds that the Korean income subsidy has a negative effect on farm efficiency. Our results provide two policy implications for the government of Korea. First, even though the &ldquo, Returns to the Farm and Rural program&rdquo, is appropriate, Korea should modify the program to encourage more young people to participate this program rather than old people, in order to attain the sustainable development of the agricultural sector. Second, a policy maker in Korea should consider a coupled subsidy that is directly related to farm production rather than a decoupled subsidy, regardless of the lower efficiency of the coupled subsidy in achieving agricultural development.

Pendred syndrome (PS) is an autosomal recessive disorder characterized by congenital bilateral sensorineural hearing loss, goiter, and incomplete iodide organification. Patients with PS also have structural anomalies of the inner ear such as enlarged vestibular aqueducts (EVA) and Mondini's malformation. The goiter, which is a major clinical manifestation of PS, usually develops around adolescence. PS is caused by biallelic mutations of the SLC26A4 gene, while nonsyndromic bilateral EVA is associated with zero or one SLC26A4 mutant allele. We report here a Korean family including a young female with PS who had goiter and progressive, fluctuating sensorineural hearing loss that could be partially recovered by oral steroid treatment. Genetic investigation revealed compound heterozygous mutations for p.R677AfsX11, a novel frameshift mutation, and p.H723R in the SLC26A4 gene. Our findings provide detailed information regarding the distribution of mutant alleles for PS and may serve as a foundation for studies to comprehend the genetic portion of syndromic hearing loss.

Received February 5, 2013 Revised March 7, 2013 Accepted March 8, 2013 Address for correspondence Dongbin Ahn, MD Department of OtolaryngologyHead and Neck Surgery, Kyungpook National University Medical Center, 807 Hoguk-ro, Buk-gu, Daegu 702-210, Korea Tel +82-53-200-5777 Fax +82-53-423-4524 E-mail godlikeu@naver.com Background and ObjectivesZZPyriform sinus fistula with 3 and 4 branchial cleft anomaly is an extremely rare congenital condition that is not very well understood owing to its rarity. The aim of the study was to review our experience with pyriform sinus fistulae to better understand them. Subjects and MethodZZOf 163 patients with branchial anomaly treated at our institute between 1999 and 2011, medical records of 15 patients with pyriform sinus fistula were retrospectively reviewed. ResultsZZOverall, 9.2% had pyriform sinus fistulae and this proportion was higher than that of patients with 1st branchial anomaly. The mean age at the time of initial symptom presentation was 11.9 years. However, five patients (33.3%) were not diagnosed at that time because pyriform sinus fistula was not suspected. Computed tomography (CT) was the most sensitive diagnostic tool in patients suspected to have pyriform sinus fistulae; the sensitivity of CT was 86.7%, whereas that for esophagography was only 20%. Conservative surgical treatment involving cauterization of the opening of the fistula tract was performed in nine patients and showed favorable results with 22.2% of recurrence rate during a mean follow-up period of 23.1 months. In 67.7% of the patients, the causative organisms were bacteria inhabiting human mouth, suggesting that infection source for pyriform sinus fistula may be food contents and discharge of upper aerodigestive tract. ConclusionZZThe incidence of pyriform sinus fistula may be higher than expected. Therefore, the possibility of pyriform sinus fistulae coexisting should be considered while treating young patients with perithyroidal infection. Korean J Otorhinolaryngol-Head Neck Surg 2013;56:154-8

Background and Objectives:The Angio-Seal (a St. Jude Medical Co., USA) hemostatic puncture closure device produces direct femoral arterial hemostasis, by anchoring a collagen plug to the anterior vascular wall, through a sheath delivery system. The rapid and effective hemostasis leads to earlier ambulation, minimized hospital stay, patient discomfort and vascular complications. This study was performed to evaluate the efficacy and complications of an Angio-Seal in patients undergoing coronary angiography and angioplasty. Subjects and Methods:A total 228 consecutive patients, admitted to our hospital for percutaneous coronary intervention, between October 2001 and May 2002, were enrolled and randomized into 2 groups. 116 patients were treated with an Angio-Seal and the other 112 with manual compression only (control group). The clinical characteristics, procedure related factors, time to ambulation, times to outpatient discharge and complications were analyzed in each patient. All the clinical and procedure-related factors, leading to oozing and delayed bleeding, were also analyzed in the 113 patients who had a successfully completed Angio-Seal deployment. Results:The times to ambulation (7.96±5.81 hours vs. 23.32±3.35 hours) and times to outpatient discharge (2.00±0.94 days vs. 3.47 ±3.61 days) were significantly shorter in the Angio-Seal compared to the control group (p=0.001 & p=0.001, respectively). There was oozing in 20 patients (17.7%) and delayed bleeding in 6 (5.3%) of the successful AngioSeal deployment group. The occurrence of oozing was significantly higher in the heparin infusion cases (40% vs. 18.3%, p=0.034), and was correlated with a later hematoma formation rate and the size of the hematoma (30% vs. 9.7%, 0.68±1.26 cm vs. 0.17±0.70 cm, p=0.015 & p=0.001, respectively). Delayed bleeding was correlated to the hematoma occurrence rate (50% vs. 11.2%, p=0.006). Conclusion:The Angio-Seal resulted in earlier ambulation and shorten the patients’ hospital stay. Oozing, delayed bleeding, hematomas were noted as complications. Oozing and delayed bleeding were correlated with a high hematoma occurrence rate. Careful inspection of the puncture sites, following an Angio-Seal deployment, should be performed. (Korean Circulation J 2003;33 (7):574-582)

Background and Objectives：Coronary stents have been used increasingly in the field of coronary intervention. However, in-stent restenosis (ISR remains a therapeutic challenge. The subsequent response to repeat intervention in the restenotic lesion may be predicted by the angiographic pattern of ISR. In particular, the restenosis rate following re-intervention in this lesion is higher. This study evaluated the incidence of restenosis types and the predictors for diffuse type ISR. Subjects and Methods：The study population included 66 patients with in-stent restenotic lesions after stent implantation. Angiographic restenosis was defined as a diameter stenosis of ≥50% at follow-up coronary angiography. Patterns of ISR were defined as focal type (

Background:Percutaneous mitral balloon valvuloplasty (PMV) has been proposed as an alternative to surgery for selected patients with symptomatic mitral stenosis. The presence of mild mitral regurgitation (MR) in mitral stenosis is usually not considered as a contraindication for the procedure. But, the results of PMV in the subgroup of patients with concomitant mild MR are unknown. Accordingly, this study evaluates the clinical outcome of a consecutive series of patients with mitral stenosis and mild MR undergoing PMV. Methods:Between August 1992 and December 1996 we attempted to dilate the mitral valves of 43 consecutive patients with symptomatic mitral stenosis. Mean age of the group was 45.9±10.6 years and 37 patients were women. They were divided into two groups according to the presence or absence of mild MR before the procedure. Clinical feature, inital result, complication were compared. Results:1) Age, gender, symptomatic status, and atrial fibrillation were similar in both groups. 2) Patients with MR had more thickened valve (2.50±0.33 vs 1.84±0.55, p=0.048) and subvalvular tissue (2.55±0.73 vs 1.88±0.73, p=0.015), higher echocardiographic score (8.44±1.01 vs 7.08±1.65, p=0.004). 3) Mitral valve area gain on the first day after PMV was smaller in patients with MR (p=0.008). 4) The success rate of PMV, the incidence of severe MR after PMV, and the restenosis rate on 6 month were similar in both groups. Conclusion:Although the PMV in patients with mild MR obtained smaller increments in mitral valve area compared to those without MR, they showed similar immediate and short-term results after PMV. (Korean Circulation J 1999;29(6):596-601)

Background and Objectives:The myocardial protective effect of ischemic preconditioning is well known. However, the mechanism is remains unclear. The purpose of this study is to determine the role of adenosine, protein kinase C, KATP channel and the change of monophasic action potential duration on cardioprotective effect of ischemic preconditioning in cat. Materials and Methods:In this experiment, 66 cats were allocated into 7 groups:control (n=10, ischemic preconditioning (n=10, adenosine pre-treated (n=10, SPT (8-p- sulfophenyl theophylline pre-treated (n=9, polymyxin B pre-treated (n=9, glibenclamide pre-treated (n= 9 and nicorandil pre-treated (n=9 groups. Ischemic preconditioning was performed in ischemic precondi- tioning, SPT pre-treated, polymyxin B pre-treated and glibenclamide pre-treated groups by 3 episodes of 5 minutes ischemia and 10 minutes reperfusion. All animals were subjected to 40 minutes of ischemia and 40 minutes of reperfusion. Monophasic action potential duration at 50% repolarization (MAP50 was measured in the ischemic and non-ischemic area respectively by epicardial probe throughout the experiment. The effect of ischemic preconditioning was determined by infarct size (% area at risk. Results:Ischemic preconditioning, adenosine pre-treatment and nicorandil pre-treatment groups demonstrated a significant reduction in infarct size (26±4%, 25±4% and 34±8% infarction of the risk zone, respectively, p

Typhoid fever is an acute systemic febrile disease caused by Salmonella typhi. The classic picture of the disease consists of prolonged continuous or remitting fever, abdominal pain, diarrhea, rose spots and delirium. Salmonella infection can lead to diffuse organ involvement., including bone, lung, thyroid, kidney, liver, spleen, heart, pericardium, intestine and skin and cause a variety of complications. Pulmonary manifestations occur in only 1 percent of the patients. Mild cough with sticky sputum is the earliest symptom and bronchitis, pneumonia and lung abscess were presented. Recently we experienced a case of typhoid fever complicated by bronchitis, dysplasia in a 37-year-old male physician who was improved with ceftriaxone and ciprofloxacin We report this case with a review of the literature.

Background:The aging of the patient population is one of the most important factors influencing health care delivery. Currently 5% of the Korean population is elderly, defined as older than 65 years of age, with this group projected to increase to 13.1% by the year 2021. Cardiovascular disease is the leading cause of death and of disability in the elderly age group. Among them, coronary heart disease is the most important. Method:Study population composed of 216 patients who were admittied to the hospital with first acute myocardial infarction and they were divided into two groups according to the age(older than 65 years of age vs younger). Clinical features, risk factors of coronary heart disease, in-hospital outcome and complication were compared in elderly patients and others group. Results: 1) The risk factors of coronary heart disease is similar to younger patients but pattern of chest pain is less typical than younger patients. 2) Clinical presentation of elderly patients is similar to younger patients except Killip class on admission.(1.66 vs 1.91, p=0.04) 3) In-hospital mortality of elderly patients in higher than younger patients. In addition to an increased incidence of death, recurrent ischemia, stroke, AV block, ventricular arrythmia, pulmonary edema occured more frequently with advanced age. 4) Especially in the thrombolytic therapy group, in-hospital death, reinfarction and recurrent ischemia is higher than primary PTCA group in elderly patients. Conclusions:Diagnosis of acute chest pain is difficult in elderly patients and in-hospital mortality and morbidity is higher than in younger patients. Thus more accurate diagnosis and discriminative therapeutic modality is needed.