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Tolerance Range Analysis of Fish on Chemical Water Quality in Aquatic Ecosystems

  • Kim, Jeong-Kyu;Han, Jeong-Ho;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.43 no.4
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    • pp.459-470
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    • 2010
  • In this study, we analyzed fish tolerance guilds in mainstems and tributaries of 65 streams and rivers arid their relations to water quality using dataset sampled from April to November, 2009. For the study, water quality parameters including biochemical oxygen demand (BOD), electric conductivity (EC), total nitrogen (TN), total phosphorus (TP), ammonia nitrogen ($NH_3$-N), nitrate nitrogen ($NO_3$-N) and phosphate phosphorus ($PO_4$-P) were analyzed in the laboratory and also tolerance ranges in 3 category fishes of sensitive, intermediate, and tolerant species with high abundance were analyzed. According to fish guild analysis, tolerant species was 58% of the total community and the proportion of omnivore species was 63% of the total, indicating a degradation of habitats and water quality. Water quality was shown typical longitudinal gradients from the headwater to the down-river; TN and TP increased toward the down-rivers except for the big point-source area and ionic contents, based on, electric conductivity showed same pattern. Tolerance guild analysis of 9 major species with high abundance indicated that sensitive groups had narrower tolerance range in the water quality than the groups of intermediate and tolerant species. In contrast, tolerant groups including Zacco platypus, Carassius auratus, and Opsarichthys uncirostris amurensis had wider tolerance ranges than the groups of sensitive and intermediate species. Thus, each group was evidently segregated from the tolerance levels. Principal Component Analysis (PCA) employed for the relations of water quality to fish species in each groups suggests that water quality had highest eigenvalues with fish species in the 1st axis of the PCA and nitrogen (TN, $NH_3$-N, $NO_3$-N) and phosphorus (TP) were key components differentiating three groups of sensitive, intermediate and tolerance guilds.

The Comparative Study on the Frequency of Transcutaneous Electrical Nerve Stimulation for Delayed-Onset Muscle Soreness (지연성 근육통에 대한 경피신경전기자극의 주파수별 효과 비교)

  • Park, Hyun-Gun;Lee, Jong-Soo
    • Journal of Korean Medicine Rehabilitation
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    • v.23 no.2
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    • pp.63-72
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    • 2013
  • Objectives : The aim of this study was to investigate difference of the effects of transcutaneous electrical nerve stimulation(TENS) with different frequencies in participants having delayed onset muscle soreness(DOMS). Methods : We recruited 36 healthy participants, but 3 of them were dropped out. They were randomly divided into 3groups : 3 Hz TENS(n=11), 100 Hz TENS(n=11) and sham TENS(n=11). DOMS of the both triceps surae muscle induced by repetitive concentric, ecentric exercise. The result measurements were pain perception(visual analogue scale, VAS), mechanical pain threshold(MPT) by pressure algometer, electrical contraction and fatigue by surface electromyography. The measurements were on first visit, before and after treatment except first. This study was prospective, randomized, controlled, single-blinded trial. Results : In 100 Hz TENS group, VAS was significantly decreased during whole session compared with 3 Hz and control group, and after each treatment, too. In 3 Hz TENS group, VAS was significantly decreased during whole session compared with control group, and after 2nd, 3rd treatment, too. In 100 Hz TENS group, MPT increased the most among 3 groups during whole session and after 1st treatment, but there were no statistical significances. Conclusions : Both 3 Hz and 100 Hz TENS improved delayed onset muscle soreness, but 100 Hz TENS group is more effective than 3 Hz TENS group.

COMPARATIVE STUDY ON THE FRACTURE STRENGTH OF METAL-CERAMIC VERSUS COMPOSITE RESIN-VENEERED METAL CROWNS IN CEMENT-RETAINED IMPLANT-SUPPORTED CROWNS UNDER VERTICAL COMPRESSIVE LOAD

  • Pae, Ahran;Jeon, Kyung-A;Kim, Myung-Rae;Kim, Sung-Hun
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.3
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    • pp.295-302
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    • 2007
  • Statement of problem. Fracture of the tooth-colored superstructure material is one of the main prosthetic complications in implant-supported prostheses. Purpose. The purpose of this in vitro study was to compare the fracture strength between the cement-retained implant-supported metal-ceramic crowns and the indirect composite resinveneered metal crowns under the vertical compressive load. Material and methods. Standard implants of external type (AVANA IFR 415 Pre-mount; Osstem Co., Busan, Korea) were embedded in stainless steel blocks perpendicular to their long axis. Customized abutments were fabricated using plastic UCLA abutments (Esthetic plastic cylinder; Osstem Co., Busan, Korea). Thirty standardized copings were cast with non-precious metal (Rexillium III, Pentron, Walling ford, Conn., USA). Copings were divided into two groups of 15 specimens each (n = 15). For Group I specimens, metal-ceramic crowns were fabricated. For Group II specimens, composite resin-veneered (Sinfony, 3M-ESPE, St. Paul, MN, USA) metal crowns (Sinfony-veneered crowns) were fabricated according to manufacturer's instructions. All crowns were temporary cemented and vertically loaded with an Instron universal testing machine (Instron 3366, Instron Corp., Norwood, MA, USA). The maximum load value (N) at the moment of complete failure was recorded and all data were statistically analyzed by independent sample t-test at the significance level of 0.05. The modes of failure were also investigated with visual analysis. Results. The fracture strength of Sinfony-veneered crowns ($2292.7{\pm}576.0N$) was significantly greater than that of metal-ceramic crowns ($1150.6{\pm}268.2N$) (P < 0.05). With regard to the failure mode, Sinfony-veneered crowns exhibited adhesive failure, while metal-ceramic crowns tended to fracture in a manner that resulted in combined failure. Conclusion. Sinfony-veneered crowns demonstrated a significantly higher fracture strength than that of metal-ceramic crowns in cement-retained implant-supported prostheses.

The Formation of the Shallow Junction by RTD and Characteristic Analysis for $n^+$ -p Diode with Ti-silicide (고속 열 확산에 의한 얕은 접합 형성과 Ti-실리시이드화된 $n^+$ -p 다이오드 특성 분석)

  • 최동영;이성욱;주정규;강명구;윤석범;오환술
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.31A no.8
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    • pp.80-90
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    • 1994
  • The ultra shallow junction was formed by 2-step RTP. Phosphorus solid source(P$_{2}O_{5}$) was transfered on wafer surface during RTG(Rapid Thermal Glass Transfer) of which process condition was 80$0^{\circ}C$ and 60sec. The process temperature and time of the RTD(Rapid Thermal Diffusion) were 950~105$0^{\circ}C$ during 5~15sec respectively sheet resistances were measured as 175~320$\Omega$/m and junction depth and dopth and dopant surface concentration were measured as 0.075~0.18$\mu$m and 5${\times}10^{19}cm^{4}$ respectively. Ti-silicide was formed by 2-step RTA after 300$\AA$ Titanium was deposited. The 1st RTA (2nd RTA) was carried out at the temperature of $600^{\circ}C$(700~80$0^{\circ}C$) for 30 seconds (10~60 seconds) under N$_2$ ambient. Sheet resistances after 2nd RTA were measured as 46~63$\Omega$/D. Si/Ti component ratio was evaulated as 1.6~1.9 from Auger depth profile. Ti-Silicided n-p junction diode (pattern size : 400$\times$400$\mu$m) was fabricated under the RTD(the process was carried out at the temperature of 100$0^{\circ}C$ for 10seconds) and 2nd RTA(theprocess was carried out at the temperature of 750$^{\circ}C$ for 60 seconds). Leakage current was measured 1.8${\times}10^{7}A/mm^{2}$ at 5V reverse voltage. Whent the RTD process condition is at the temperature of 100$0^{\circ}C$ for 10seconds and the 2nd RTA process condition is at the temperature of 75$0^{\circ}C$ for 60 seconds leakage current was 29.15${\times}10^{9}A$(at 5V).

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The effect of resin cements and primer on retentive force of zirconia copings bonded to zirconia abutments with insufficient retention

  • Kim, Seung-Mi;Yoon, Ji-Young;Lee, Myung-Hyun;Oh, Nam-Sik
    • The Journal of Advanced Prosthodontics
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    • v.5 no.2
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    • pp.198-203
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    • 2013
  • PURPOSE. The purpose of this study was to investigate the effect of resin cements and primer on the retentive force of zirconia copings bonded to zirconia abutments with insufficient retention. MATERIALS AND METHODS. Zirconia blocks (Lava, 3M ESPE, St. Paul, MN, USA) were obtained and forty sets of zirconia abutments and copings were fabricated using CAD/CAM technology. They were grouped into 4 categories as follows, depending on the types of resin cements used, and whether the primer is applied or not:Panavia F2.0 (P), Panavia F2.0 using Primer (PRIME Plus, Bisco Inc, Schaumburg, IL, USA) (PZ), Superbond C&B (S), and Superbond C&B using Primer (SZ). For each of the groups, the cementation was conducted. The specimens were kept in sterilized water ($37^{\circ}C$) for 24 hours. Retentive forces were tested and measured, and a statistical analysis was carried out. The nature of failure was recorded. RESULTS. The means and standard deviations of retentive force in Newton for each group were $265.15{\pm}35.04$ N (P), $318.21{\pm}22.24$ N (PZ), $445.13{\pm}78.54$ N (S) and $508.21{\pm}79.48$ N (SZ). Superbond C&B groups (S & SZ) showed significantly higher retentive force than Panavia F2.0 groups (P & PZ). In Panavia F2.0 groups, the use of primer was found to contribute to the increase of retentive force. On the other hand, in Superbond C&B groups, the use of primer did not influence the retention forces. Adhesive failure was observed in all groups. CONCLUSION. This study suggests that cementation of the zirconia abutments and zirconia copings with Superbond C&B have a higher retentive force than Panavia F2.0. When using Panavia F2.0, the use of primer increases the retentive force.

Current Status of Biological Nursing Science Education for Clinical Nurses in General Hospital (종합병원 임상간호사 실무교육에서의 기초간호학 교육현황)

  • Jeong, Jae Sim;Hwang, Young Hui;Kim, Yongbum;Ryu, Jae Geum;Kim, Mi Kyung;Choi, So-Eun;Park, Myung Sook;Lee, Hyangkyu;Lee, Kyung-Sook;Choi-Kwon, Smi
    • Journal of Korean Biological Nursing Science
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    • v.20 no.1
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    • pp.47-53
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    • 2018
  • Purpose: The purpose of this study was to investigate the extent and the nature of biological nursing science education for clinical nurses in general hospital. Methods: Five advanced general hospitals located in Seoul and Gyeonggi province were conveniently sampled. Contents of education for nurses conducted by the hospital nursing department from January 1 to December 31 of 2015 were collected. Contents of education included biological nursing science and the scope of inclusion and time of assignment were analyzed. Results: A total of 271 cases of nursing education data were collected and 223 cases were analyzed after excluding 48 cases whose contents were not confirmed. Biological nursing science was included in the contents of education for 117 cases (52.5%), but not for 106 cases (47.5%). Regarding the frequency of the biological nursing science education contents, 'pathophysiology'was the most frequently included (n= 286), followed by 'structure and function of the human body' (n= 191), 'mechanisms and effects of drugs' (n= 114) and 'clinical microbiology' (n= 43). Conclusion: Results of this study confirmed that the education for clinical nurses included a lot of biological nursing science related contents. These results can be used as basis for the development of curriculum and training course for nurses.

Surface Modification of Polymer Films by Vapor Phase Photografting of Functional Monomers (기상 UV 그라프트 반응에 의한 고분자 필름의 표면 개질)

  • Oh, Seung Hee;Oh, Se Heang;Lee, Jin Ho
    • Journal of Adhesion and Interface
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    • v.1 no.1
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    • pp.23-29
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    • 2000
  • Surface modification of hydrophobic polymeric materials to be hydrophilic or to have specific functional groups is of great importance for a diversity of applications of the materials. In this study, polyethylene (PE) film surfaces were modified by vapor phase photografting of hydrophilic vinyl monomers with different functional groups. The functional monomers were introduced on PE films by introducing the monomers in vapor phase using a vapor phase photografting apparatus designed by our laboratory. Functional monomers used were acrylic acid (negatively chargeable), acrylamide and allylalcohol (neutral), and allylamine and N,N-dimethyl aminopropyl acryamide (positively charged). The functional monomer-grafted PE film surfaces were characterized by the measurement of water contact angles and the attenuated total reflectance Fourier-transform infrared spectroscopy. The vapor phase photografting seems to be effective means for introduction of various functional groups onto polymeric substrates.

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Research on the emission of electromagnetic waves in ambulance (구급차량 내 전자파 방출에 관한 조사)

  • Yun, Jong-Geun
    • The Korean Journal of Emergency Medical Services
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    • v.23 no.1
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    • pp.61-69
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    • 2019
  • Purpose: The study aims to provide basic data to enhance the health of paramedics responsible for patient transport and treatment by analyzing the exposure level of paramedics to electromagnetic waves generated by electric devices used in ambulances. Methods: The study measured electromagnetic waves in ambulances in N region from July to December 2018. ME3030B produced by German Gigahertz Solutions was used to measure these waves and the maximum value was selected by moving it slowly in various directions. Each measurement part was selected and the mean value was calculated by repeatedly measuring at 10-minute intervals three times in total: $1^{st}$, $2^{nd}$, and $3^{rd}$ phase. Results: Among the electrical devices installed in the patient room of the ambulance measured at distances of 1 cm or 30 cm, results showed a high level of electric waves at the inverter ($26.25{\pm}39V/m$) and high level of electromagnetic waves ($564.00{\pm}31.75nT$) at the ozone sterilizer. According to measurements toward the front near the driver's seat, results indicated high levels of electric waves ($3.67{\pm}1.15V/m$) and electromagnetic waves ($450.00{\pm}19.52nT$) at the black box hard drive. Conclusion: Electromagnetic waves within the ambulance were stable and not beyond the range that might impact human health. However, in the case of the black box hard drive ($3.67{\pm}1.15V/m$, $450.00{\pm}19.52nT$) located under the passenger seat, it may have a direct effect on the human body and, thus it is necessary to move it to a storage area further away from the paramedics to minimized the impact.

Is Completion Thyroidectomy Necessary in Patients with Papillary Thyroid Carcinoma who Underwent Lobectomy? (엽절제술을 시행한 갑상선 유두암 환자에서 완결 갑상선 절제술이 필요한지에 대한 연구)

  • Kang, Il Ku;Kim, Kwangsoon;Bae, Ja Seong;Kim, Jeong Soo
    • Korean Journal of Head & Neck Oncology
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    • v.37 no.2
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    • pp.25-31
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    • 2021
  • Background/Objectives: Although thyroid lobectomy recently is considered as sufficient for low-risk papillary thyroid carcinoma (PTC), completion thyroidectomy is required due to the insufficiency of the preoperative evaluation. The aim of this study was to investigate recurrence rate and disease free survival depending on the gross extrathyroidal extension (gETE) or the number of metastatic lymph node identified in patients with PTC. Materials & Methods: We assessed 3373 patients with PTC who underwent lobectomy at Seoul St. Mary's Hospital (Seoul, Korea) between January 2009 and December 2014. Clinicopathological characteristics and long-term surgical outcomes were retrospectively analyzed through complete chart reviews. The mean follow-up duration was 97.1 ± 21.4 months. Results: The rate of recurrence was higher in gETE group (1.8% vs. 6.0%, p=0.004), leading to decreased disease free survival in Kaplan-Meier analysis (log-rank p<0.001). N1 group (n=1389) was analyzed into two groups whether the number of positive nodes is more than 5 or less. For the group of the more metastatic nodes, the recurrence rate higher compared to the other group (3.0% vs. 9.3%, p<0.001). DFS was longer in the group that had lesser metastatic nodes (log-rank p<0.001). However, in terms of N1 group over 1cm (n=492), No statistical difference was observed according to the number of positive lymph nodes (4.5% vs. 9.1%, p=0.092) Conclusion: When it comes to node positive PTC, Despite the number of positive lymph nodes was over 5, follow-up with no further surgery can be an option.

Molecular subtyping and antimicrobial susceptibility of Streptococcus dysgalactiae subspecies equisimilis isolates from clinically diseased pigs

  • Oh, Sang-Ik;Kim, Jong Wan;Kim, Jongho;So, Byungjae;Kim, Bumseok;Kim, Ha-Young
    • Journal of Veterinary Science
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    • v.21 no.4
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    • pp.57.1-57.11
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    • 2020
  • Background: Streptococcus dysgalactiae subspecies equisimilis (SDSE) acts as an etiological agent for lameness, neurological signs, and high mortality in pigs. Despite its importance in pig industries and zoonotic potential, little is known about the effects of this pathogen. Objectives: This study aimed to determine the molecular characteristics and antimicrobial resistance of SDSE strains isolated from diseased pigs. Methods: A total 11 SDSE isolates were obtained from diseased pigs. Bacterial identification, PCR for virulence genes, emm typing, and antimicrobial resistance genes, multilocus sequence typing, and antimicrobial susceptibility test were performed. Results: Nine isolates were from piglets, and 8 showed lameness, sudden death, or neurological signs. The isolates were PCR-positive for sla (100%), sagA (100%), and scpA (45.5%), and only 1 isolate amplified the emm gene (stL2764). Eight different sequence types were detected, categorized into 2 clonal complexes and 4 singletons. All the isolates in this study were included in a small cluster, which also contained other strains derived from humans and horses. The minimum inhibitory concentrations for the tested beta-lactams were low, while those for macrolides, tetracyclines, and fluoroquinolones were relatively high. PCR analysis of the macrolide and tetracycline resistance genes demonstrated that the isolates carried erm(B) (18.2%, n = 2), mef(A/E) (9.1%, n = 1), tet(M) (18.2%, n = 2), and tet(O) (90.2%, n = 10). Two isolates presented a mutation in parC, which is associated with fluoroquinolone resistance. Conclusion: This study provided insight into swine-derived SDSE, as it is related to veterinary medicine, and elucidated its zoonotic potential, in the context of molecular epidemiology and antimicrobial resistance in public health.