Technical Efficiency in the Iron and Steel Industry: A Stochastic Frontier Approach

In this paper we examine the technical efficiency of firms in the iron and steel industry and try to identify the factors contributing to the industry's efficiency growth, using a time-varying stochastic frontier model. Based on our findings, which pertain to 52 iron and steel firms over the period of 1978-1997, POSCO and Nippon Steel were the most efficient firms, with their production, on average, exceeding 95 percent of their potential output. Our findings also shed light on possible sources of efficiency growth in the industry. If a firm is government-owned, its privatization is likely to improve its technical efficiency to a great extent. A firm's technical efficiency also tends to be positively related to its production level as measured by a share of the total world production of crude steel. Another important source of efficiency growth identified by our empirical findings is adoption of new technologies and equipment. Our findings clearly indicate that continued efforts to update technologies and equipment are critical in pursuit of efficiency in the iron and steel industry.

In Vitro Chemosensitivity Using the Histoculture Drug Response Assay in Human Epithelial Ovarian Cancer

The choice of chemotherapeutic drugs to treat patients with epithelial ovarian cancer has not depended on individual patient characteristics. We have investigated the correlation between in vitro chemosensitivity, as determined by the histoculture drug response assay (HDRA), and clinical responses in epithelial ovarian cancer. Fresh tissue samples were obtained from 79 patients with epithelial ovarian cancer. The sensitivity of these samples to 11 chemotherapeutic agents was tested using the HDRA method according to established methods, and we analyzed the results retrospectively. HDRA showed that they were more chemosensitive to carboplatin, topotecan and belotecan, with inhibition rates of 49.2%, 44.7%, and 39.7%, respectively, than to cisplatin, the traditional drug of choice in epithelial ovarian cancer. Among the 37 patients with FIGO stage Ⅲ/Ⅳ serous adenocarcinoma who were receiving carboplatin combined with paclitaxel, those with carboplatin-sensitive samples on HDRA had a significantly longer median disease-free interval than patients with carboplatin- resistant samples (23.2 vs. 13.8 months, p＜0.05), but median overall survival did not differ significantly (60.4 vs. 37.3 months, p＝0.621). In conclusion, this study indicates that HDRA could provide useful information for designing individual treatment strategies in patients with epithelial ovarian cancer

Evaluation of Creep-fatigue Damage for Heat Exchangers in the Stella Sodium Test Loop

AbstractCreep-fatigue damage evaluation of DHX (Decay Heat Exchanger) and AHX(Air Heat Exchanger) in the sodium test facility has been performed. The sodium test loop of the STELLA-1 is for component performance tests of the main components, heat exchangers and mechanical pumps which are to be installed in an integral sodium test loop (STELLA-2) for simulating thermal hydraulic decay heat removal behaviour of the Korean demonstration Sodium-cooled Fast Reactor. High temperature design and fabrication of the DHX and AHX have been conducted and the components were installed at KAERI site. Evaluation of creep-fatigue damage at critical locations of the two heat exchangers were conducted according to the elevated temperature design codes of the ASME-NH and RCC-MR and the evaluation results were compared

The Effects of Athletes’ Imposter Syndrome Tendency on Achievement Goal Orientation and Regulatory Focus

PURPOSE This study aimed to verify the influence of imposter syndrome tendencies in athletes on their achievement goal orientation, and regulatory focus. METHODS Data collected from 413 athletes through surveys were analyzed using SPSS version 27.0 and AMOS version 21.0 to assess reliability and validity, conduct independent sample t-tests, perform correlation analysis, and conduct multiple regression analyses. RESULTS The findings revealed significant sex-based differences in imposter syndrome tendencies, achievement goal orientation, and regulatory focus. Moreover, significant correlations were observed between sub-factors of imposter syndrome, achievement goal orientation, and regulatory focus. Imposter syndrome tendencies had varying effects on achievement goal orientation, with the discount factor significantly influencing approach orientation, the fake factor significantly affecting avoidance orientation, and fear factors significantly impacting self-avoidance. Additionally, imposter syndrome tendencies influenced regulatory focus, as the discount factor significantly affected both promotion focus and prevention focus, while fake and fear factors significantly influenced prevention focus. CONCLUSIONS This study underscores the importance of athletes' imposter syndrome tendencies as significant contributors to psychological variables related to motivation, including achievement goal orientation and regulatory focus

Protein Tyrosine Phosphatases as Potential Regulators of STAT3 Signaling

The signal transducer and activator of transcription 3 (STAT3) protein is a major transcription factor involved in many cellular processes, such as cell growth and proliferation, differentiation, migration, and cell death or cell apoptosis. It is activated in response to a variety of extracellular stimuli including cytokines and growth factors. The aberrant activation of STAT3 contributes to several human diseases, particularly cancer. Consequently, STAT3-mediated signaling continues to be extensively studied in order to identify potential targets for the development of new and more effective clinical therapeutics. STAT3 activation can be regulated, either positively or negatively, by different posttranslational mechanisms including serine or tyrosine phosphorylation/dephosphorylation, acetylation, or demethylation. One of the major mechanisms that negatively regulates STAT3 activation is dephosphorylation of the tyrosine residue essential for its activation by protein tyrosine phosphatases (PTPs). There are seven PTPs that have been shown to dephosphorylate STAT3 and, thereby, regulate STAT3 signaling: PTP receptor-type D (PTPRD), PTP receptor-type T (PTPRT), PTP receptor-type K (PTPRK), Src homology region 2 (SH-2) domain-containing phosphatase 1(SHP1), SH-2 domain-containing phosphatase 2 (SHP2), MEG2/PTP non-receptor type 9 (PTPN9), and T-cell PTP (TC-PTP)/PTP non-receptor type 2 (PTPN2). These regulators have great potential as targets for the development of more effective therapies against human disease, including cancer