Innovation and Internationalization of Korean SMEs in the Textile and Footwear Industries

Innovation has been recognized as one of the factors that enhances firm internationalization, a vital route for the growth and survival of small and medium enterprises. Thus, it is important to identify antecedents of firm innovation and their impacts on SME internationalization for their long-term success. Accordingly, the present study examined a model of SME internationalization in which the causal relationships among entrepreneurial orientation, absorptive capacity, innovation (product, process, and marketing innovation), and internationalization were proposed. Analyses of 156 survey data collected from Korean SMEs exporting textiles, apparel, and footwear revealed that entrepreneurial orientation and absorptive capacity appeared to function as significant antecedents of product and process innovation. Among three dimensions of innovation, only process and marketing innovation positively affected internationalization. The study provides practical implications by asserting the importance of process and marketing innovation to increase firm internationalization

Development of selective blockers for Ca2+-activated Cl- channel using Xenopus laevis oocytes with an improved drug screening strategy

<p>Abstract</p> <p>Background</p> <p>Ca²⁺-activated Cl^-channels (CaCCs) participate in many important physiological processes. However, the lack of effective and selective blockers has hindered the study of these channels, mostly due to the lack of good assay system. Here, we have developed a reliable drug screening method for better blockers of CaCCs, using the endogeneous CaCCs in <it>Xenopus laevis </it>oocytes and two-electrode voltage-clamp (TEVC) technique.</p> <p>Results</p> <p>Oocytes were prepared with a treatment of Ca²⁺ionophore, which was followed by a treatment of thapsigargin which depletes Ca²⁺stores to eliminate any contribution of Ca²⁺release. TEVC was performed with micropipette containing chelerythrine to prevent PKC dependent run-up or run-down. Under these conditions, Ca²⁺-activated Cl^-currents induced by bath application of Ca²⁺to oocytes showed stable peak amplitude when repetitively activated, allowing us to test several concentrations of a test compound from one oocyte. Inhibitory activities of commercially available blockers and synthesized anthranilic acid derivatives were tested using this method. As a result, newly synthesized <it>N</it>-(4-trifluoromethylphenyl)anthranilic acid with trifluoromethyl group (-CF₃) at <it>para </it>position on the benzene ring showed the lowest IC₅₀.</p> <p>Conclusion</p> <p>Our results provide an optimal drug screening strategy suitable for high throughput screening, and propose <it>N</it>-(4-trifluoromethylphenyl)anthranilic acid as an improved CaCC blocker.</p

Biological Responses to Diesel Exhaust Particles (DEPs) Depend on the Physicochemical Properties of the DEPs

Diesel exhaust particles (DEPs) are the main components of ambient particulate materials, including polyaromatic hydrocarbons (PAHs), n-PAHs, heavy metals, and gaseous materials. Many epidemiological, clinical, and toxicological studies have shown that ambient particles, including DEPs, are associated with respiratory disorders, such as asthma, allergic rhinitis, and lung cancer. However, the relationship between the biological response to DEPs and their chemical composition remains unclear. In this study, we investigated the physicochemical properties of DEPs before toxicological studies, and then administered a single intratracheal instillation of DEPs to mice. The mice were then killed 1, 7, 14 and 28 days after DEP exposure to observe the biological responses induced by DEPs over time. Our findings suggest that DEPs engulfed into cells induced a Th2-type inflammatory response followed by DNA damage, whereas DEPs not engulfed into cells induced a Th1-type inflammatory response. Further, the physicochemical properties, including surface charge, particle size, and chemical composition, of DEPs play a crucial role in determining the biological responses to DEPs. Consequently, we suggest that the biological response to DEPs depend on cell-particle interaction and the physicochemical properties of the particles

Biological Toxicity and Inflammatory Response of Semi-Single-Walled Carbon Nanotubes

The toxicological studies on carbon nanotubes (CNTs) have been urgently needed from the emerging diverse applications of CNTs. Physicochemical properties such as shape, diameter, conductance, surface charge and surface chemistry of CNTs gained during manufacturing processes play a key role in the toxicity. In this study, we separated the semi-conductive components of SWCNTs (semi-SWCNTs) and evaluated the toxicity on days 1, 7, 14 and 28 after intratracheal instillation in order to determine the role of conductance. Exposure to semi-SWCNTs significantly increased the growth of mice and significantly decreased the relative ratio of brain weight to body weight. Recruitment of monocytes into the bloodstream increased in a time-dependent manner, and significant hematological changes were observed 28 days after exposure. In the bronchoalveolar lavage (BAL) fluid, secretion of Th2-type cytokines, particularly IL-10, was more predominant than Th1-type cytokines, and expression of regulated on activation normal T cell expressed and secreted (RANTES), p53, transforming growth factor (TGF)-β, and inducible nitric oxide synthase (iNOS) increased in a time-dependent manner. Fibrotic histopathological changes peaked on day 7 and decreased 14 days after exposure. Expression of cyclooxygenase-2 (COX-2), mesothelin, and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) also peaked on day 7, while that of TGF-β peaked on days 7 and 14. Secretion of histamine in BAL fluid decreased in a time-dependent manner. Consequently, we suggest that the brain is the target organ of semi-SWCNTs brought into the lung, and conductance as well as length may be critical factors affecting the intensity and duration of the inflammatory response following SWCNT exposure

Structural and Dynamical Characteristics of Short-Chain Branched Ring Polymer Melts at Interface under Shear Flow

We present a detailed analysis of the interfacial chain structure and dynamics of confined polymer melt systems under shear over a wide range of flow strengths using atomistic nonequilibrium molecular dynamics simulations, paying particular attention to the rheological influence of the closed-loop ring geometry and short-chain branching. We analyzed the interfacial slip, characteristic molecular mechanisms, and deformed chain conformations in response to the applied flow for linear, ring, short-chain branched (SCB) linear, and SCB ring polyethylene melts. The ring topology generally enlarges the interfacial chain dimension along the neutral direction, enhancing the dynamic friction of interfacial chains moving against the wall in the flow direction. This leads to a relatively smaller degree of slip (ds) for the ring-shaped polymers compared with their linear analogues. Furthermore, short-chain branching generally resulted in more compact and less deformed chain structures via the intrinsically fast random motions of the short branches. The short branches tend to be oriented more perpendicular (i.e., aligned in the neutral direction) than parallel to the backbone, which is mostly aligned in the flow direction, thereby enhancing the dynamic wall friction of the moving interfacial chains toward the flow direction. These features afford a relatively lower ds and less variation in ds in the weak-to-intermediate flow regimes. Accordingly, the interfacial SCB ring system displayed the lowest ds among the studied polymer systems throughout these regimes owing to the synergetic effects of ring geometry and short-chain branching. On the contrary, the structural disturbance exerted by the highly mobile short branches promotes the detachment of interfacial chains from the wall at strong flow fields, which results in steeper increasing behavior of the interfacial slip for the SCB polymers in the strong flow regime compared to the pure linear and ring polymers

Post-Intubation Tracheoesophageal Fistula with Posterior Glottic Web

Tracheoesophageal fistula (TEF) after prolonged intubation could present as chronic aspiration and could be mistaken as unilateral or bilateral vocal fold palsy, especially when there was combined posterior glottic synechia. We present a case of post-intubation TEF which was successfully treated with tracheal resection and anastomosis with primary esophageal closure. The accompanying posterior glottic web was treated by endoscopic technique of web lysis, with topical application of mitomycin C solution

A More Appropriate Cardiac Troponin T Level That Can Predict Outcomes in End-Stage Renal Disease Patients with Acute Coronary Syndrome

Purpose: Cardiac troponin T (cTnT), a useful marker for diagnosing acute myocardial infarction (AMI) in the general population, is significantly higher than the usual cut-off value in many end-stage renal disease (ESRD) patients without clinically apparent evidence of AMI. The aim of this study was to evaluate the clinical usefulness of cTnT in ESRD patients with acute coronary syndrome (ACS). Materials and methods: Two hundred eighty-four ESRD patients with ACS were enrolled between March 2002 and February 2008. These patients were followed until death or June 2009. Medical records were reviewed retrospectively. The cut-off value of cTnT for AMI was evaluated using a receiver operating characteristic (ROC) curve. We calculated Kaplan-Meier survival curves, and potential outcome predictors were determined by Cox proportional hazard analysis. Results: AMIs were diagnosed in 40 patients (14.1%). The area under the curve was 0.98 in the ROC curve (p<0.001; 95% CI, 0.95-1.00). The summation of sensitivity and specificity was highest at the initial cTnT value of 0.35 ng/mL (sensitivity, 0.95; specificity, 0.97). Survival analysis showed a statistically significant difference in all-cause and cardiovascular mortalities for the group with an initial cTnT ≥0.35 ng/mL compared to the other groups. Initial serum cTnT concentration was an independent predictor for mortality. Conclusion: Because ESRD patients with an initial cTnT concentration ≥0.35 ng/mL have a poor prognosis, it is suggested that urgent diagnosis and treatment be indicated in dialysis patients with ACS when the initial cTnT levels are ≥0.35 ng/mL.ope

A Case of Hypersensitivity to Mosquito Bite Associated with Epstein-Barr Viral Infection and Natural Killer Cell Lymphocytosis

Hypersensitivity to mosquito bites (HMB) is a disorder characterized by a necrotic skin reaction and generalized symptoms subsequent to mosquito bites. It has been suggested that HMB is associated with chronic Epstein-Barr virus (EBV) infection and natural killer cell leukemia/lymphoma. We describe here a Korean child who had HMB associated with chronic EBV infection and natural killer cell lymphocytosis. A 5-yr-old boy was suffered from necrotic skin lesions on the right ear lobe. Type A EB virus was detected from hlood cells and bone marrow biospy recognized hemophagocyrosis

A Useful Predictor of Early Atherosclerosis in Obese Children: Serum High-sensitivity C-reactive Protein

Childhood obesity seems to contribute to the development of vascular inflammation and the progression of arterial wall changes. High-sensitivity C-reactive protein (hs-CRP) has recently emerged as a useful biomarker for vascular inflammation associated with atherosclerosis. The objectives of this study were to evaluate the association of the serum hs-CRP level with ultrasonic findings of early atherosclerosis, carotid intima-media wall thickness (IMT) and brachial flow-mediated dilation (FMD), in obese children. Thirty eight obese children and 45 sex/age-matched healthy control children were recruited. Serum CRP levels were measured by the high-sensitive latex turbidimetric immunoassay, and we measured carotid IMT and brachial FMD using high-resolution B-mode ultrasonography. Obese children had significantly higher hs-CRP levels (1.40±0.74 mg/L vs. 0.55±0.49 mg/L, p<0.01), as well as increased IMT (0.52±0.09 mm vs. 0.41±0.07 mm, p<0.01) and impaired FMD (7.35±7.78% vs. 20.34±16.81%, p<0.01) compared to healthy controls. Serum hs-CRP correlated positively with IMT (r=0.413, p<0.05) and inversely with FMD (r=-0.350, p<0.05) in the obesity group. Measurement of the serum hs-CRP level is a simple, cheap, and highly reproducible assay and correlates with IMT and FMD in obese children. Thus, it would be a useful marker for evaluating and estimating the degree of atherosclerosis in children