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191.
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193.
Jin Sook Kim Hyun Jeong Jeon Kyung Min Lee Jung Nam Im Ji Ho Youk 《Fibers and Polymers》2010,11(2):153-157
Polyacrylonitrile (PAN) nanoparticles were successfully prepared by dispersion polymerization of acrylonitrile (AN) in water
using 10 and 20 wt% of the poly(ethylene oxide)-b-PAN macromolecular RAFT (PEO-b-PAN macro-RAFT) agent (M
n=5,600 g/mol, PDI=1.15). The degrees of polymerization of the PEO and PAN blocks were 113 and 16, respectively. The PAN nanoparticles
had a crumpled spherical appearance and their sizes ranged from 50–80 nm. The degree of crystallinity of the PAN particles
was 23 %. The M
n
values of the PAN nanoparticles prepared with 10 and 20 wt% of the PEO-b-PAN macro-RAFT agent were 33,900 and 25,800 g/mol, respectively. The existence of the PEO block on the surface of the PAN
nanoparticles was confirmed by 1H NMR spectroscopy and XPS. 相似文献
194.
Sangkeun Son Sung-Kyun Ko Mina Jang Jong Won Kim Gil Soo Kim Jae Kyoung Lee Eun Soo Jeon Yushi Futamura In-Ja Ryoo Jung-Sook Lee Hyuncheol Oh Young-Soo Hong Bo Yeon Kim Shunji Takahashi Hiroyuki Osada Jae-Hyuk Jang Jong Seog Ahn 《Marine drugs》2016,14(4)
Salterns, one of the most extreme natural hypersaline environments, are a rich source of halophilic and halotolerant microorganisms, but they remain largely underexplored ecological niches in the discovery of bioactive secondary metabolites. In continued efforts to investigate the metabolic potential of microbial populations from chemically underexplored sites, three new lipopeptides named iturin F1, iturin F2 and iturin A9 (1–3), along with iturin A8 (4), were isolated from Bacillus sp. KCB14S006 derived from a saltern. The structures of the isolated compounds were established by 1D-, 2D-NMR and HR-ESIMS, and their absolute configurations were determined by applying advanced Marfey’s method and CD spectroscopy. All isolates exhibited significant antifungal activities against various pathogenic fungi and moderate cytotoxic activities toward HeLa and srcts-NRK cell lines. Moreover, in an in vitro enzymatic assay, compound 4 showed a significant inhibitory activity against indoleamine 2,3-dioxygenase. 相似文献
195.
196.
Kim JS Lee BH Jang IS Jeon HJ Kim HY Han JS Lee YL Lee MJ 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):907-912
Despite numerous benefits of laparoscopic procedures, the serious hypercapnia and respiratory acidosis in hypercapnic patients with decreased pulmonary compliance during carbon dioxide-induced pneumoperitoneum (CDP) may be developed. Tracheal gas insufflation (TGI) has been shown to be a useful adjunct to controlled mechanical hypoventilation. This study was undertaken to identify whether TGI superimposed on controlled mechanical ventilation (CMV) improve ventilatory efficiency during CDP in rabbits. Sixteen paralyzed and anesthetized rabbits were used. The animals were assigned to two groups-CMV group: CMV alone; TGI group: CMV superimposed by TGI with flow rate of 2L/min. The animals were insufflated to intra-abdominal pressure of 8 mmHg with CO2 gas. Then, tidal volume (V(T)) was changed to maintain the set peak inspiratory pressure (PIP) value, while other ventilatory settings were kept constant. The set PIP value corresponding to 30, 60, and 90 min after the start of peritoneal insufflation of CO2 were 15, 22, and 25 cm H2O, respectively. During CDP with TGI, PaCO2 decreased significantly (p<0.01) from CMV without TGI of 82.1 +/- 14.1 to 47.5 +/- 5.5, 58.1 +/- 9.9 to 40.0 +/- 4.6, 47.1 +/- 9.4 to 32.7 +/- 5.1 mmHg at PIP of 15, 22, and 25 cm H2O, respectively. The inspired V(T) decreased significantly (p<0.05) from CMV without TGI of 18.4 +/- 3.9 to 12.8 +/- 2.8 ml at PIP of 15 cm H2O. TGI superimposed on CMV is more effective than CMV alone in enhancing ventilatory efficiency during CDP in rabbits. 相似文献
197.
Effects of dietary phytoncides extracted from Korean pine (Pinus koraiensis) cone on performance,egg quality,gut microflora,and immune response in laying hens
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Min‐Jeong Kim U‐Suk Jung Jae‐Sung Lee Seung‐Woo Jeon Won‐Seob Kim Byoung‐Ki An Eun‐Jib Kim Tao Wang Bae‐Young Kim Jin‐Taek Im Hong‐Gu Lee 《Journal of animal physiology and animal nutrition》2018,102(5):1220-1231
This study was conducted to evaluate the effects of dietary phytoncides extracted from discarded Korean pine cones (Pinus koraiensis) on the performance, egg quality, immune response and gut microflora in laying hens. A total of 400 Hy‐Line brown laying hens (50‐week old) were allotted into four dietary treatments including a control diet or a diet supplemented with phytoncides at 0.002%, 0.004% and 0.008%. During the 6 weeks of experimental feeding, 0.008% of dietary phytoncides improved egg production, feed conversion ratio (p < 0.05), but not feed intake, egg weight or feed efficiency. Although dietary phytoncides had no effect on egg quality, decreases in Haugh units depending on storage periods were improved by 0.008% of dietary phytoncides (p < 0.05). To investigate the roles of dietary phytoncides on the alteration of the immune response during inflammation, lipopolysaccharide (LPS) or saline was intraperitoneally injected into 10 hens per diet group on the end date of the experimental feeding period. Serum immunoglobulins and splenic cytokine expression at mRNA levels were then measured at 4 hr postinjection. Although the levels of IgA were decreased by LPS injection in all dietary groups, dietary phytoncides at 0.008% showed a higher level of IgA by LPS (p < 0.05). Interestingly, although LPS injection resulted in an enhanced expression of proinflammatory cytokines such as IL‐1β and IL‐6, dietary phytoncides at 0.008% showed less increased levels of them (p < 0.05). Gut microflora was examined from 10 hens per diet group at the end of the experimental period. While the number of Lactobacillus spp. was increased (p < 0.05), Escherichia coli counts in the cecal contents were decreased by 0.008% of dietary phytoncides. Taken together, these results demonstrate that dietary supplementation of 0.008% phytoncides improved the egg production, immune responses during inflammation and gut microflora in laying hens. 相似文献
198.
In this study, dimensional characteristics of core spun cotton/spandex interlock structures with high, medium and low tightness
factors were studied under dry-, wet-, and full relaxation conditions. Results are compared with those for similar fabrics
knitted from 100 % cotton. Dimensional characteristics of samples of core-spun cotton/spandex and cotton are measured by considering
the changing of course-, wale- densities and stitch densities under dry, wet and full relaxation conditions. Based on these
data, dimensional constants (U-values) were predicted under 95 % significance level. Higher U-values are reported with cotton/spandex
interlocks than 100 % cotton and under full relaxation, cotton/spandex shows the U-values with lesser CV%. Stitch density
growth is linearly correlated with tightness factor for both interlock material structures. Excellent resiliency property
of cotton/spandex yarns increases tightness factors at machine off state and during relaxation states. Cotton/spandex interlock
structures show more prominent co-relationship with their tightness factors on their dimensional parameters. 相似文献
199.
R. Nirmala Kyung Soo Jeon R. Navamathavan Mira Park Hak Yong Kim Soo-Jin Park 《Fibers and Polymers》2014,15(5):918-923
In this study, we describe the preparation and characterization of electrospun Nylon66 composite nanofibers incorporated with carbon nanotubes (CNT) fillers and silver nanoparticles. We have incorporated the composites in to Nylon66 nanofibers to enhance the characteristics of the resultant composite nanofibers. The resultant composite nanofibers were characterized by using field-emission scanning electron microscopy, energy dispersive X-ray analysis, high-resolution transmission electron microscopy, X-ray diffraction, and current-voltage (I–V) measurement analysis. The morphology of the composite nanofibers exhibited densely arranged mesh-like ultrafine nanofibers which were strongly bound in between the main fibers. From I–V characteristics, it was observed that the incorporation of CNT fillers and Ag nanoparticles in to electrospun Nylon66 composite nanofibers can be significantly enhanced the electrical properties. 相似文献
200.
Seung-Yeol Jeon Woong-Ryeol Yu Min Sun Kim Joon Seok Lee Jong Won Kim 《Fibers and Polymers》2014,15(6):1202-1210
As nonwoven mats are randomly oriented fiber assemblies, the tensile strength of nonwoven mats is determined by their microstructural factors, such as fiber orientation, fiber volume fraction, and fiber-fiber contact level. The complex microstructure of nonwoven mats must be reasonably simplified to properly predict their mechanical properties within affordable efforts. In this study, a new parameter, so called contact efficiency, is defined to describe the fiber-fiber contact level of nonwoven mats. Micro X-ray computer tomography (CT) is employed to characterize the microstructure of needlepunched nonwoven mats made of polypropylene short fibers. The fiber orientation and volume fraction are obtained by analyzing 2D sectional CT image of the nonwoven mat, while the contact efficiency is determined from 3D CT image. A statistical model, developed originally for staple yarns, is modified to predict the tensile strength of the nonwoven mat using the microstructural factors obtained from CT analysis. The prediction is then compared with experiments to validate that the current model incorporating the contact efficiency is highly suitable for predicting the tensile strength of nonwoven mats. 相似文献