• 열처리공학회지
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• 제14권1호
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• pp.27-34
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• 2001

The effects of pre-heat treatment(Q/T) on microstructure and hardness of STD11 and STD61 tool steel nitrided by micro-pulse plasma were investigated. The quenching temperature for obtaining matrix hardness of STD11 and STD61 steel on range of HRC 50 to HRC 60 desired for machine parts is about $1070^{\circ}C$ and $1020^{\circ}C$ respectively. The hardness of STD11 and STD61 quenched at the temperature was HRC 63 and HRC 56 respectively. The nitrided case depth of STD11 and STD61 nitrided at $550^{\circ}C$ for 5 hours was independent of pre-heat treatment condition and the depth was approximately $100{\mu}m$. However, hardness and compactness of nitrided layer on Q/T treated specimen were higher than the annealed specimen. The case depth increased linearly with the increase of nitriding temperature, however, the hardness of nitrided layer decreased with the increase of temperature. Phase mixture of ${\gamma}-Fe_4N$ and ${\varepsilon}-Fe_{2-3}N$ was detected by XRD analysis in the nitrided layer formed at the optimum nitriding condition. The optimum nitriding temperature was approximately $490^{\circ}C$ which was $10^{\circ}C$ lower than the tempering temperature for preventing softening behavior of STD11 and STD61 matrix during nitriding process and the surface hardness of nitrided layer obtained by optimum pre-heat treatment condition was about Hv1400.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제20권2호
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• pp.94-99
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• 2017

Purpose: Abdominal cysts of gastrointestinal origin are rare. Their rarity and varied clinical presentations make their pre-operative diagnosis difficult. Methods: Fourteen patients with histological diagnosis of cysts of gastrointestinal origin admitted between 2009 and 2015 were retrospectively analyzed with respect to age, sex, clinical presentation, diagnostic modality, site and type of cyst, management, outcome and follow-up. Results: The mean age at presentation was 4 years and there were six males and eight females. Abdominal pain was the most common presenting symptom. Five patients had an acute presentation-three had distal ileal mesenteric cysts and two had ileal duplication cyst sharing a common wall with ileum. Six patients presented with chronic abdominal pain and lump-three patients had omental cysts and three had mesenteric cysts-two of these in distal ileum and one in sigmoid colon. Two patients presented with antenatally diagnosed palpable abdominal lump. One had a mesenteric cyst of the ileum and the other had a distal ileal duplication cyst which required excision with resection and anastomosis. One patient had an atypical presentation. He was a known case of sickle cell trait and had presented with vague abdominal pain, recurrent cough and multiple episodes of haemoptysis over a period of one year. At laparotomy, gastric duplication cyst was found which was excised completely. Histopathology confirmed the diagnosis. Conclusion: Cysts of gastrointestinal origin are rare and have varied presentation. Surgical excision is the mainstay of treatment. The results and prognosis are good.

• Safety and Health at Work
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• 제3권2호
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• pp.117-122
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• 2012

Objectives: To describe the time perspective of return to work and the factors that facilitate and hinder return to work in a group of survivors of acute coronary syndrome (ACS). Methods: Retrospective semi-structured telephone survey 2 to 3 years after hospitalization with 84 employed Dutch ACS-patients from one academic medical hospital. Results: Fifty-eight percent of patients returned to work within 3 months, whereas at least 88% returned to work once within 2 years. Two years after hospitalization, 12% of ACS patients had not returned to work at all, and 24% were working, but not at pre-ACS levels. For all ACS-patients, the most mentioned categories of facilitating factors to return to work were having no complaints and not having signs or symptoms of heart disease. Physical incapacity, co-morbidity, and mental incapacity were the top 3 categories of hindering factors against returning to work. Conclusion: Within 2 years, 36% of the patients had not returned to work at their pre-ACS levels. Disease factors, functional capacity, environmental factors, and personal factors were listed as affecting subjects' work ability level.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1998년도 춘계 학술대회논문집
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• pp.123-127
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• 1998

A computer code has been developed for an analysis of conduction and convection heat transfer on a personal computer. FVM based on unstructured mesh has been employed for triangular and quadrilateral element. All variable of p, u, v, T, k and ${\varepsilon}$ has been defined on a node (not on a center of element). The code possesses the pre-and post-processor for itself to provide user-friendly interface.

• The Journal of Korean Physical Therapy
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• 제22권5호
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• pp.103-108
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• 2010

Purpose: The aim of this study is to investigate whether motor cortex excitability by transcranial direct current stimulation (tDCS) over primary motor cortex (M1) affects motor performance of serial reaction task. Methods: Cathodal, anodal and sham tDCS (1 mA) are applied over right M1 of 24 subjects for 30 minutes including 11minutes for task period time. We applied two electrodes at the same position to both an experimental group and a sham-controlled group, and we made 2 groups recognize to be applicated of stimulation. Flexion, extension of wrist and thumb flexion are carried out following colors of arrows on the monitor. Serial reaction time task was applied to confirm the difference of the reaction time between 2 groups. Results: Reaction time is decreased in both tDCS-group and Sham-controlled tDCS group, and the degree of reduction is much greater in the post-test than pre-test. Reduction of reaction time between groupsis statistically significant. Conclusion: We consider that anodal tDCS increased the cortical excitability of the underlying motor cortex and it can be helpful to modulate motor performance. It seems that tDCS is an effective modality to modulate brain function, and it will be great help to mediate strategy for the brain injury patients.

• IUGG한국위원회:학술대회논문집
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• IUGG한국위원회 2003년도 정기총회 및 학술발표회
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• pp.20-20
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• 2003

In the summers of 1997 and 1998 and in February of 2000 we made 570 measurements of the ambient geomagnetic field 120 cm above the pavement surface of State Route 130, south of Pahoa, the island of Hawaii using a three-component fluxgate magnetometer. We measured at every 15.2 m (50 feet) interval covering a distance of 6, 310 m (20, 704 ft) where both historic and pre-historic highly magnetic basalt flows underlie. We also collected 197 core samples from eight road cuts, 489 specimens of which were subject to AF demagnetizations at 5 - 10 mT level up to a maximum field of 60 mT. We observed significant inclination anomalies ranging from a minimum of $31^{\circ}$ to a maximum $40^{\circ}$ where a uniform inclination value of $36.7^{\circ}$ (International Geomagnetic Reference Field, IGRF) was expected. Since the mean of the observed inclinations is approximately $35^{\circ}$ we assume that the study area is slightly affected by the magnetic terrain effect to a systematically shallower inclinations for being located in the regionally sloping surface of the southern side of the island (Baag, et al., 1995). We observed inclination anomalies showing wider (spacial) wavelength (160 - 600 m) and higher amplitudes in the historic lava flows area than in the northern pre-historic flows. Our observations imply that preexisting inclination anomalies such as those that we observed would have been interpreted as paleosecular variation (PSV). These inclination anomalies can best be attributed to concealed underground highly magnetic dikes, channel type lava flows, on-and-off hydrothermal activities through fissure-like openings, etc. Both the within- and between-site dispersions of natural remanent magnetization (NRM) are largest (up to ${\pm}7^{\circ}$) above the flows of 1955, while the area of pre-historic flows in the northern part of the study area exhibit the smallest dispersion. Nevertheless, mean inclinations of each historic flow of 1955 and 1790 are almost identical to that of the corresponding present field, whereas mean of NRM (after AF demagnetization) inclinations for each of the four pre-historic lava flow units is twelve to thirteen degrees lower than the present field inclination. We observed three cases of very large inclination variations from within a single flow, the best fitting curves of which are linear, second and third order polynomials each from within a single flow, whereas no present field variations are observed. This phenomena can be attributed to the notion that local magnetic anomalies on the surface of an active volcano are not permanent, but are transient. Therefore we believe that local magnetic anomalies of an active volcano may be constantly modified due to on going subsurface injections and circulations of hot material and also due to wide spacial and temporal distribution of highly magnetic basaltic flows that will constantly modify the topography which will in turn modify the local ambient geomagnetic field (Baag, et al., 1995). Our observations bring into question the general reliability of PSV data inferred from volcanic rocks, because on-going various geologic and geophysical activities associated with active volcano would continuously deflect and modify the ambient geomagnetic field.

• 대한수학회보
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• 제46권5호
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• pp.867-871
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• 2009

A module M over a ring R is said to satisfy (P) if every generating set of M contains an independent generating set. The following results are proved; (1) Let $\tau$ = ($\mathbb{T}_\tau,\;\mathbb{F}_\tau$) be a hereditary torsion theory such that $\mathbb{T}_\tau$ $\neq$ Mod-R. Then every $\tau$-torsionfree R-module satisfies (P) if and only if S = R/$\tau$(R) is a division ring. (2) Let $\mathcal{K}$ be a hereditary pre-torsion class of modules. Then every module in $\mathcal{K}$ satisfies (P) if and only if either $\mathcal{K}$ = {0} or S = R/$Soc_\mathcal{K}$(R) is a division ring, where $Soc_\mathcal{K}$(R) = $\cap${I 4\leq$ $R_R$ : R/I$\in\mathcal{K}$}.

• The Korean Journal of Physiology and Pharmacology
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• 제21권5호
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• pp.495-507
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• 2017

The effect of clonidine administered intrathecally (i.t.) on the mortality and the blood glucose level induced by sepsis was examined in mice. To produce sepsis, the mixture of D-galactosamine (GaLN; 0.6 g/10 ml)/lipopolysaccharide (LPS; $27{\mu}g/27{\mu}l$) was treated intraperitoneally (i.p.). The i.t. pretreatment with clonidine ($5{\mu}g/5{\mu}l$) increased the blood glucose level and attenuated mortality induced by sepsis in a dose-dependent manner. The i.t. post-treatment with clonidine up to 3 h caused an elevation of the blood glucose level and protected sepsis-induced mortality, whereas clonidine post-treated at 6, 9, or 12 h did not affect. The pre-treatment with oral D-glucose for 30 min prior to i.t. post-treatment (6 h) with clonidine did not rescue sepsis-induced mortality. In addition, i.t. pretreatment with pertussis toxin (PTX) reduced clonidine-induced protection against mortality and clonidine-induced hyperglycemia, suggesting that protective effect against sepsis-induced mortality seems to be mediated via activating PTX-sensitive G-proteins in the spinal cord. Moreover, pretreatment with clonidine attenuated the plasma tumor necrosis factor ${\alpha}$ ($TNF-{\alpha}$) induced by sepsis. Clonidine administered i.t. or i.p. increased $p-AMPK{\alpha}1$ and $p-AMPK{\alpha}2$, but decreased p-Tyk2 and p-mTOR levels in both control and sepsis groups, suggesting that the up-regulations of $p-AMPK{\alpha}1$ and $p-AMPK{\alpha}2$, or down-regulations of p-mTOR and p-Tyk2 may play critical roles for the protective effect of clonidine against sepsis-induced mortality.

• International Journal of Industrial Entomology and Biomaterials
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• 제5권1호
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• pp.23-32
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• 2002

The introduction of hybrid and exploitation of heterosis has played a vital role in Indian sericulture industry, which clearly depicts a quantum jump in silk production during the last four decades. Since, the introduction of heterosis, progress in silkworm breeding has depended on success or failure in identifying better combiners. Systematic procedures developed have enabled the breeders to identify the best combiners by combining ability test, line ${\TIMES}$ tester analysis or $D^2$ analysis for maximum expression of heterosis. The level of heterosis expressed in the crossbreed population is determined by the interaction between genotype and prevailing environmental factors. Except some of the pre and post cocoon parameters, heterosis is invariably higher in single crosses compared to three-way and double crosses. However, during hot and humid season, when rearing of F1 bivoltine hybrid is unsuccessful at field level and indigenous races results in very low and poor quality yield, three-way and double crosses can play an important role as an intermediary technology. The objective of this article is to review briefly the concept and causes of heterosis, utilization of different forms of heterosis in silk production and its significance in silkworm, Bombyx mori breeding.

• Asian Pacific Journal of Cancer Prevention
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• 제17권11호
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• pp.4945-4949
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• 2016

Background: Breast cancer is the commonest cancer in Egyptian females. Nrf2 is involved in oxidative stress while P73 functions in response to DNA damage. This study aimed to assess the role of Nrf2 promoter and P73 G4C14 to A4T14 SNPs in breast cancer in Egypt. Patients: Eighty-five female patients with breast tumours (41 malignant, 44 benign) were included. Nrf2 (rs6721961) and p73 (G4A) SNPs were determined by PCR- CTPP assay. Results: Genotype frequencies of the Nrf2 promoter SNP were 34.2% and 37.9% for AA in benign and malignant groups respectively, and 43.9% and 40.5% for CC and, 21.9 % and 21.6% for CA. Genotype frequencies for the P73 G4A SNP were 52.9% and 44.7% for GA in benign and malignant groups respectively, and 47.1% and 55.3% for GG. Discussion: Nrf2 genotypes in pre - and post-menopausal patients, showed significantly different distributions in the 2 patient groups, the AA genotype being significantly more common in pre-menopausal patients. The P73 G4A SNP showed no relation to age of disease onset. Conclusion: The Nrf2 (rs6721961) AA genotype might be related to early breast cancer onset. In contrast the P73 G4A polymorphism showed no relation to either disease risk or age at presentation.