• 융합경영연구
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• 제11권5호
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• pp.15-27
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• 2023

Purpose: Taking Tesla Motors as a case study object, this research aims to summarize the management strategy of Tesla Motors through an evaluation of its business models in Korea and China then helps other new energy automobile enterprises in formulating strategic directions in a targeted manner. Research design, data and methodology: Using the case study method, this study conducts in-depth research on the business model of Tesla, a representative enterprise of the new energy automobile industry. This study mainly uses secondary data obtained from the official websites to support our research. Results: With its top-level innovative technology, distinctive marketing model, and extensive strategic model, Tesla holds the largest share of the new energy vehicle market. Local market brands such as BYD and Hyundai-Kia still have a considerable competitive advantage, and there is a need to learn from each other for further development. Conclusions: To adapt to the needs of economic transformation and environmental development, implementing business strategies related to new energy automobile enterprises is a topic worthy of study. Enterprises such as BYD and Hyundai-Kia have unique advantages in their home markets. However, as sustainable development progresses, these advantages will gradually weaken, and further measures are necessary to maintain their competitive advantage.

• 인지과학
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• 제16권1호
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• pp.1-15
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• 2005

인간의 시각 체계는 제한된 용량으로 인해 매 순간 입력되는 정보들 중에 필요한 일부 정보만을 선택하는 주의 기제를 사용한다. 최근의 여러 연구들은 주의가 요구되는 시각 탐색 과제에서 탐색 자극에 대한 기억이 주의의 이동 과정에 사용될 수 있음을 보고해 왔다(Chun & Jiang, 1998, 1999; Klein, 1988; Klein 1998; Maclnnes, 1999). 하지만 다른 일련의 연구들은, 인간의 시각 정보 유지능력이 순간적으로 일어나는 시각적 변화를 잘 탐지하지 못할 뿐 아니라(Rensink, O'Regan, & Clark, 1997; Simons & Levin, 1997), 시각 탐색에서도 기억이 형성되지 못해, 이미 탐색한 대상에 대한 재탐색이 계속적으로 이루어짐을 주장하였다(Horowitz & Wolfe, 1998). 본 연구에서는 시각 탐색 과정에서 이미 탐색한 자극이나 그 위치에 대한 기억이 사용되어 탐색 효율성에 영향을 주는지 알아보기 위해, 재탐색을 할 수 없도록 제한한 탐색조건(부분 노출 조건, 확장 노출 조건)을 새로 고안하여 이들 조건에서의 탐색 효율성이 기존의 탐색 방식을 제한하지 않는 탐색 조건(전체 노출 조건)에서의 탐색 효율성과 어떤 차이를 보이는지를 비교하였다. 만일 일반적인 탐색 환경인 전체 노출 조건에서 재탐색이 일어난다면, 재탐색이 일어나지 않도록 조작한 다른 조건에 비해 탐색 효율성이 떨어질 것으로 예상하였다. 실험 결과, 탐색 효율성은 탐색 조건에 상관없이 비슷하게 나타났다. 이러한 결과는 실험 참가자들 이 전체 노출 조건에서도 탐색했던 대상에 대해서 재탐색을 거의 하지 않았음을 의미하는 것이며, 따라서 탐색 과정에서 기억이 사용되고 있는 것으로 해석할 수 있다. 본 연구 결과는 시각 탐색에 기억이 사용되지 않는다는 최근의 일부 연구 결과와 상반된 것으로서, 기존 연구 패러다임의 문제점과 가능한 해석들을 논의하였다.

• Safety and Health at Work
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• 제14권4호
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• pp.457-466
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• 2023

Background: During hot environment work tasks with whole-body enclosed anti-bioaerosol suit, the combined effect of heavy sweating and exhaled hot humid air may cause the N95 medical respirator to saturate with water/sweat (i.e., water-blocking). Methods: 32 young male subjects with different body mass indexes (BMI) in whole-body protection (N95 medical respirator + one-piece protective suit + head covering + protective face screen + gloves + shoe covers) were asked to simulate waste collecting from each isolated room in a seven-story building at 27-28℃, and the weight, inhalation resistance (R_f), and aerosol penetration of the respirator before worn and after water-blocking were analyzed. Results: All subjects reported water-blocking asphyxia of the N95 respirators within 36-67 min of the task. When water-blocking occurred, the R_f and 10-200 nm total aerosol penetration (P_t) of the respirators reached up to 1270-1810 Pa and 17.3-23.3%, respectively, which were 10 and 8 times of that before wearing. The most penetration particle size of the respirators increased from 49-65 nm before worn to 115-154 nm under water-blocking condition, and the corresponding maximum size-dependent aerosol penetration increased from 2.5-3.5% to 20-27%. With the increase of BMI, the water-blocking occurrence time firstly increased then reduced, while the R_f, P_t, and absorbed water all increased significantly. Conclusions: This study reveals respirator water-blocking and its serious negative impacts on respiratory protection. When performing moderate-to-high-load tasks with whole-body protection in a hot environment, it is recommended that respirator be replaced with a new one at least every hour to avoid water-blocking asphyxia.

• Asian-Australasian Journal of Animal Sciences
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• 제15권4호
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• pp.555-564
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• 2002

Twenty Landrace and twenty Min piglets, with an average initial body weight of 22.4 kg, were randomly divided into 5 groups with 4 animals per group, within each of the breeds. The piglets were housed in individual concrete pens. Each group of the piglets was fed one of 5 diets. The diets contained either 20% raw Argentine soybeans, 20% processed Argentine soybeans ($118^{\circ}C$ for 7.5 min.), 20% raw Chinese soybeans, 20% processed Chinese soybeans ($118^{\circ}C$ for 7.5 min.) or no soybean products (control diet). Faecal samples were collected on days 6, 7 and 8 of the treatment period. Digestibilities of dietary nutrients were determined with AIA (acid insoluble ash) as a marker. After a 17 day treatment, three piglets were killed from each of the groups. Tissue samples of small and large intestine for light and electron microscopy examination were taken immediately after the opening of abdomen. Then, the weight or size of relevant organs was measured. The results show that the digestibilities of dry matter (DM), crude protein (CP) and fat were higher in Min piglets than in Landrace piglets (p<0.05). The diets containing processed soybeans had a significant higher CP digestibility than the control diet and the diets containing raw soybeans (p<0.05). Landrace piglets had heavier and longer small intestines, heavier kidneys and a lighter spleen than Min piglets (p<0.05). The pancreas of the animals fed the diets containing processed soybeans was heavier than that of the animals fed control diet (p<0.05) and the diets containing raw soybeans. But, the differences between raw and processed soybean diets were not significant. A significant interaction (p<0.05) between diet and pig breed was observed in weight of the small intestine. The Landrace piglets increased the weight in their small intestine when they were fed the diets containing soybeans. In the light micrographs and electron scanning micrographs, it was found that the villi of small intestinal epithelium of animals (especially Landrace piglets) fed the diets containing raw Chinese soybeans were seriously damaged. The transmission electron micrograph showed that a lot of vesicles were located between the small intestinal microvilli of these piglets. The histological examination also indicated that the proportion of goblet cells in villi and crypts in the piglets consuming the control diet was significantly lower (p<0.01 and p<0.02, respectively) than those of the animals consuming the diets containing raw or processed soybeans.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.6123-6128
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• 2015

Background: The aim of this study was to analyze the prognostic implications of pretreatment circulating endothelial cells (CECs) and circulating endothelial progenitor cells (CEPCs) for the survival of patients with lung cancer. Materials and Methods: Relevant literature was identified using Medline and EMBASE. Patient clinical characteristics, overall survival (OS) and progression-free survival (PFS) together with CEC and CEPC positive rates before treatment were extracted. STATA 12.0 was used for our analysis and assessment of publication bias. Results: A total of 13 articles (8 for CEC and 5 for CEPC, n=595 and n=244) were pooled for the global meta-analysis. The odds ratio (OR) for OS predicted by pretreatment CECs was 1.641 [0.967, 2.786], while the OR for PFS was 1.168 [0.649, 2.100]. The OR for OS predicted by pretreatment CEPCs was 12.673 [5.274, 30.450], while the OR for PFS was 4.930 [0.931, 26.096]. Subgroup analyses were conducted according to clinical staging. Odds ratio (OR) showed the high level of pretreatment CECs only correlated with the OS of patients with advanced lung cancer (stage III-IV). Conclusions: High counts of CECs seem to be associated only with worse 1-year OS in patients with lung cancer, while high level of pretreatment CEPCs correlate with both worse PFS and OS.

• The Korean Journal of Physiology and Pharmacology
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• 제18권4호
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• pp.353-358
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• 2014

Control of blood pressure is maintained by the interaction between the arterial baroreflex and vestibulosympathetic reflex during postural changes. In this study, the contributions of vestibular receptors and baroreceptors to the maintenance of blood pressure following acute hypotension were compared in terms of phosphorylated extracellular regulated protein kinase (pERK) expression in the nucleus tractus solitaries (NTS). Expression of pERK in the NTS was measured in conscious rats that had undergone bilateral labyrinthectomy (BL) and/or sinoaortic denervation (SAD) 5, 10, 20, and 40 min following acute hypotension induced by sodium nitroprusside (SNP) infusion. Expression of pERK increased significantly in the NTS in the control group following SNP infusion, and the expression peaked at 10 min after SNP infusion. The number of pERK positive neurons increased following SNP infusion in BL, SAD, and BL+SAD groups, although the increase was smaller than in control group. The BL group showed a relatively higher reduction in pERK expression than the SAD group, and the pERK expression in the NTS was localized to the caudal portion of the nuclei in the BL and SAD groups. These results suggest that the vestibular receptors may play a key role in maintaining blood pressure following acute hypotension; thus, the vestibular system may contribute to compensate for orthostatic hypotension.

• The Plant Pathology Journal
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• 제32권5호
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• pp.414-422
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• 2016

Eucalyptus dieback disease, caused by Cylindrocladium scoparium, has occurred in last few years in large Eucalyptus planting areas in China and other countries. Rapid, simple, and reliable diagnostic techniques are desired for the early detection of Eucalyptus dieback of C. scoparium prior to formulation of efficient control plan. For this purpose, three PCR-based methods of nested PCR, multiplex PCR, loop-mediated isothermal amplification (LAMP) were developed for detection of C. scoparium based on factor 1-alpha (tef1) and beta-tubulin gene in this study. All of the three methods showed highly specific to C. scoparium. The sensitivities of the nested PCR and LAMP were much higher than the multiplex PCR. The sensitivity of multiplex PCR was also higher than regular PCR. C. scoparium could be detected within 60 min from infected Eucalyptus plants by LAMP, while at least 2 h was needed by the rest two methods. Using different Eucalyptus tissues as samples for C. scoparium detection, all of the three PCR-based methods showed much better detection results than regular PCR. Base on the results from this study, we concluded that any of the three PCR-based methods could be used as diagnostic technology for the development of efficient strategies of Eucalyptus dieback disease control. Particularly, LAMP was the most practical method in field application because of its one-step and rapid reaction, simple operation, single-tube utilization, and simple visualization of amplification products.

• Journal of Korean Neurosurgical Society
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• 제55권3호
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• pp.131-135
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• 2014

Objective : With the growing interests of bacteria as a targeting vector for cancer treatment, diverse genetically engineered Salmonella has been reported to be capable of targeting primary or metastatic tumor regions after intravenous injection into mouse tumor models. The purpose of this study was to investigate the capability of the genetically engineered Salmonella typhimurium (S. typhimurium) to access the glioma xenograft, which was monitored in mouse brain tumor models using optical bioluminescence imaging technique. Methods : U87 malignant glioma cells (U87-MG) stably transfected with firefly luciferase (Fluc) were implanted into BALB/cAnN nude mice by stereotactic injection into the striatum. After tumor formation, attenuated S. typhimurium expressing bacterial luciferase (Lux) was injected into the tail vein. Bioluminescence signals from transfected cells or bacteria were monitored using a cooled charge-coupled device camera to identify the tumor location or to trace the bacterial migration. Immunofluorescence staining was also performed in frozen sections of mouse glioma xenograft. Results : The injected S. typhimurium exclusively localized in the glioma xenograft region of U87-MG-bearing mouse. Immunofluorescence staining also demonstrated the accumulation of S. typhimurium in the brain tumors. Conclusion : The present study demonstrated that S. typhimurium can target glioma xenograft, and may provide a potentially therapeutic probe for glioma.

• Asian-Australasian Journal of Animal Sciences
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• 제28권12호
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• pp.1767-1773
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• 2015

Effects of water-misting sprays with forced ventilation after transport during summer on meat quality, stress parameters, glycolytic potential and microstructures of muscle in broilers were investigated. A total of 105 mixed-sex Arbor Acres broilers were divided into three treatment groups: i) 45-min transport without rest (T group), ii) 45-min transport with 1-h rest (TR group), iii) 45-min transport with 15-min water-misting sprays with forced ventilation and 45-min rest (TWFR group). The results showed the TWFR group significantly increased (p<0.05) initial muscle pH ($pH_i$) and ultimate pH ($pH_u$) and significantly reduced $L^*$ (p<0.05), drip loss, cook loss, creatine kinase, lactate dehydrogenase activity, plasma glucose content, lactate and glycolytic potential when compared with other groups. Microstructure of the muscle from TWFR group broilers under light microscopy showed smaller intercellular spaces among muscle fibers and bundles compared with T group. In conclusion this study indicated water-misting sprays with forced ventilation after transport could relieve the stress caused by transport under high temperature, which was favorable for the broilers' welfare. Furthermore, water-misting sprays with forced ventilation after transport slowed down the postmortem glycolysis rate and inhibited the occurrence of PSE-like meat in broilers. Although rest after transport could also improve the meat quality, the effect was not as significant as water-misting sprays with forced ventilation after transport.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9505-9509
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• 2014

Objective: To investigate the effects of stellate ganglion block (SGB) on the peri-operative vasomotor cytokine content and intrapulmonary shunt in patients with esophagus cancer who underwent thoracotomy. Materials and Methods: Forty patients undergoing elective resection of esophageal cancer patients who had I~II American Society of Anesthesiologist (ASA) were randomly divided into total intravenous anesthesia group (group N, n=20) and total intravenous anesthesia combined with SGB group (group S, n=20, 0.12 mL/kg 1% lidocaine was used for SGB 10 min before induction). Heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), mean pulmonary arterial pressure (MPAP) and continuous cardiac output (CCO) were continuously monitored. The blood from internal jugular vein was drawn respectively before induction ($T_0$), and 30 min ($T_1$), 60 min ($T_2$) and 120 min ($T_3$) after one-lung ventilation (OLV), and 30 min (T4) after two-lung ventilation. The contents of plasma endothelin (ET), nitric oxide (NO) and calcitonin gene-related peptide (CGRP) were detected with enzyme linked immunosorbent assay (ELISA). Meanwhile, arterial and mixed venous blood samples were collected for determination of blood gas and calculation of intrapulmonary shunt fraction (Qs/Qt). Results: During OLV, ET contents were increased significantly in two groups (P<0.05), and no significant difference was presented (P>0.05). NO content in group S was obviously higher than in group N at T3 (P<0.05), whereas CGRP content in group N was markedly lower than in group S at each time point (P<0.05). Qs/Qt was significantly increased in both groups after OLV, but there was no statistical significant regarding the Qs/Qt at each time point between two groups. Conclusions: Total intravenous anesthesia combined with SGB is conducive to regulation of perioperative vasomotor cytokines in thoracotomy, and has little effect on intrapulmonary shunt at the time of OLV.