• Title/Summary/Keyword: Chemical Union

Search Result 79, Processing Time 0.03 seconds

Sizes of Union Membership at Sector- and Industry-Levels and Their Shifts in Korea: A Micro Socioeconomic Analysis (국내의 부문 및 산업별 조합원의 규모와 그 변화 : 미시적인 사회·경제적 관점의 분석)

  • Jeong, Jooyeon
    • Journal of Labour Economics
    • /
    • v.29 no.2
    • /
    • pp.117-143
    • /
    • 2006
  • This paper illuminates the patterns of growth and declines in sizes of union membership in metal, chemical, financial, and auto transport sectors in three distinct periods during the last four decades from 1963 to 2003. This paper also calculates union densities in auto assembly, auto supply, and shipbuilding industries of the metal sector, cement, petroleum refining, and pharmaceutical industries of the chemical sector, private banking industry of the financial sector, and city bus industry of the auto transport sector. Such diversities in both sizes of union membership and union densities among sectors and industries turned out to be associated with attitudes and choices of employers and unions in interaction with sector- and industry-specific economic (growth stage and path), institutional (degrees of government intervention), and social (demographic features of employees and prevailing sizes of firms) environment. Such finding shows that theoretical reasonings on sizes of union membership and union densities across sectors and industries in advanced nations are also relevantly useful to analyze the Korean case.

  • PDF

Synthesis and Biological Evaluation of Novel Benzimidazole Derivatives Bearing a Heterocyclic Ring at 4/5 Position

  • Wubulikasimu, Reyila;Yang, Yanbing;Xue, Fei;Luo, Xianjin;Shao, Dongping;Li, Yuhuan;Gao, Rongmei;Ye, Weidong
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.8
    • /
    • pp.2297-2304
    • /
    • 2013
  • A series of novel benzimidazole derivatives bearing a heterocyclic ring as oxadiazole (21-32), thiadiazole (33-34), triazole (35-36) were synthesized and evaluated for their activities against Coxsackie virus B3 and B6 in Vero cells. Compounds 21-26, 31-36 with moieties of 2'-pyridyl, 3'-pyridyl and 4'-pyridyl at the 2-position and oxadiazoles, thiadiazole, or triazole substituent at the 4- or 5-position generally displayed activities against CVB3 and CVB6. Especially compound 24 ($IC_{50}=1.08{\mu}g/mL$, SI = 61.7 against CVB3) was the promising candidate as lead compound for anti-enteroviral drug. It was observed in the incorporation of heterocyclic rings in benzimidazole at the 5-position could enhance their biological activities.

Thiazinogeldanamycin, a New Geldanamycin Derivative Produced by Streptomyces hygroscopicus 17997

  • Ni, Siyang;Wu, Linzhuan;Wang, Hongyuan;Gan, Maoluo;Wang, Yucheng;He, Weiqing;Wang, Yiguang
    • Journal of Microbiology and Biotechnology
    • /
    • v.21 no.6
    • /
    • pp.599-603
    • /
    • 2011
  • A new geldanamycin (GDM) derivative was discovered and isolated from the fermentation broth of Streptomyces hygroscopicus 17997. Its chemical structure was elucidated as thiazinogeldanamycin by LC-MS, sulfur analysis, and NMR. The addition of cysteine to the fermentation medium significantly stimulated the production level of thiazinogeldanamycin, suggesting cysteine as a precursor of thiazinogeldanamycin production. Although showing a decreased cytotoxicity against HepG2 cancer cells, thiazinogeldanamycin exhibited an improved water solubility and photostability. Thiazinogeldanamycin may represent the first natural GDM derivative characterized so far that uses GDM as its precursor. Its appearance also clearly indicates that an appropriate end-point of fermentation is of critical importance for the maximal production of GDM by Streptomyces hygroscopicus 17997.

Dyeing of N/P Union Fabric with Reactive Disperse Dyes (반응성 분산염료를 이용한 N/P 교직물의 염색)

  • 김성동;이종렬;안창희;김규식;이권선
    • Textile Coloration and Finishing
    • /
    • v.16 no.1
    • /
    • pp.26-33
    • /
    • 2004
  • Two reactive disperse dyes having $\alpha$-bromoacrylamide or acrylamide group were synthesized and their dyeing properties were compared with a disperse dye. Dyeing properties of reactive disperse dyes were strongly influenced by the chemical structure of reactive group. The amount of absorbed reactive disperse dye containing $\alpha$-bromoacrylamide group on polyester fiber was less than the disperse dye, and that on nylon fiber was much higher. When polyester and nylon fiber were simultaneously dyed in a dye pot, nylon fiber absorbed the reactive disperse dye more than polyester fiber. The reactive disperse dye having acrylamide group could reduces difference in color depth to a large extent, but the application of carrier or variation of dyebath pH were not sufficient for giving the same color depth to both fibers. The N/P union fabric could be dyed with the reactive disperse dye and its wash fastness were good to excellent.

Biophysical therapy and biostimulation in unfavorable bony circumstances: adjunctive therapies for osseointegration

  • Kim, Yong-Deok
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.38 no.4
    • /
    • pp.195-203
    • /
    • 2012
  • Dental implants using titanium have greatly advanced through the improvement of designs and surface treatments. Nonetheless, the anatomical limits and physiological changes of the patient are still regarded as obstacles in increasing the success rate of implants further, even with the enhancement of implant products. So there have been many efforts to overcome these limits. The intrinsic potential for bone regeneration can be stimulated through adjuvant treatments with the continuous improvement of implant properties, and this can play an important role in achieving optimum osseointegration toward peripheral bone tissue and securing ultimate long-term implant stability in standard surgical procedures. For this purpose, various chemical, biological, or biophysical measures were developed such as bone grafts, materials, pharmacological agents, growth factors, and bone formation proteins. The biophysical stimulation of bone union includes non-invasive and safe methods. In the beginning, it was developed as a method to enhance the healing of fractures, but later evolved into Pulsed Electromagnetic Field, Low-Intensity Pulsed Ultrasound, and Low-Level Laser Therapy. Their beneficial effects were confirmed in many studies. This study sought to examine bone-implant union and its latest trend as well as the biophysical stimulation method to enhance the union. In particular, this study suggested the enhancement of the function of cells and tissues under a disadvantageous bone metabolism environment through such adjunctive stimulation. This study is expected to serve as a treatment guideline for implant-bone union under unfavorable circumstances caused by systemic diseases hampering bone metabolism or the host environment.

Requirement for ERK Activity in Sodium Selenite-induced Apoptosis of Acute Promyelocytic Leukemia-derived NB4 Cells

  • Han, Bingshe;Wei, Wei;Hua, Fangyuan;Cao, Tingming;Dong, Hua;Yang, Tao;Yang, Yang;Pan, Huazhen;Xu, Caimin
    • BMB Reports
    • /
    • v.40 no.2
    • /
    • pp.196-204
    • /
    • 2007
  • Our previous study has shown that sodium selenite can cause apoptosis in acute promyelocytic leukemia-derived NB4 cells in a caspase-dependent manner, but the detailed mechanism is unknown. Here we demonstrate a requirement for extracellular signal-regulated protein kinase (ERK) in mediating sodium selenite -induced apoptosis in NB4 cell. Though no apparent elevation of ERK activity was observed during the apoptosis in NB4 cells caused by 20 μM sodium selenite treatment, PD98059 and U0126, specific chemical inhibitors of the MEK/ERK signaling pathway, were shown to strongly prevent the apoptosis process, while ERK activator TPA enhanced the process. It is also known that p38 MAPK inhibitor SB203580 and JNK inhibitor SP600125 had slight effects on apoptosis. Further study indicated that ERK exerted its proapoptotic effect only at the early stage of apoptosis and played an antiapoptotic role at the later stages. Taken together, our findings suggest that ERK plays an active role in mediating sodium seleniteinduced apoptosis in NB4 cells .

A meta-analysis on advantages of peripheral nerve block post-total knee arthroplasty

  • You, Di;Qin, Lu;Li, Kai;Li, Di;Zhao, Guoqing;Li, Longyun
    • The Korean Journal of Pain
    • /
    • v.34 no.3
    • /
    • pp.271-287
    • /
    • 2021
  • Background: Postoperative pain management is crucial for patients undergoing total knee arthroplasty (TKA). There have been many recent clinical trials on post-TKA peripheral nerve block; however, they have reported inconsistent findings. In this meta-analysis, we aimed to comprehensively analyze studies on post-TKA analgesia to provide evidence-based clinical suggestions. Methods: We performed a computer-based query of PubMed, Embase, the Cochrane Library, and the Web of Science to retrieve related articles using neurothe following search terms: nerve block, nerve blockade, chemodenervation, chemical neurolysis, peridural block, epidural anesthesia, extradural anesthesia, total knee arthroplasty, total knee replacement, partial knee replacement, and others. After quality evaluation and data extraction, we analyzed the complications, visual analogue scale (VAS) score, patient satisfaction, perioperative opioid dosage, and rehabilitation indices. Evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation approach. Results: We included 16 randomized controlled trials involving 981 patients (511 receiving peripheral nerve block and 470 receiving epidural block) in the final analysis. Compared with an epidural block, a peripheral nerve block significantly reduced complications. There were no significant between-group differences in the postoperative VAS score, patient satisfaction, perioperative opioid dosage, and rehabilitation indices. Conclusions: Our findings demonstrate that the peripheral nerve block is superior to the epidural block in reducing complications without compromising the analgesic effect and patient satisfaction. Therefore, a peripheral nerve block is a safe and effective postoperative analgesic method with encouraging clinical prospects.