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        검색결과 72

        24.
        2020.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        In this work, α-Fe2O3 nanocrystals are synthesized by co-precipitation method and used as adsorbent to remove Cr6+, Cd2+, and Pb2+ from wastewater at room temperature. The prepared sample is evaluated by XRD, BET surface area, and FESEM for structural and morphological characteristics. XRD patterns confirm the formation of a pure hematite structure of average particle size of ~ 40 nm, which is further supported by the FESEM images of the nanocrystals. The nanocrystals are found to have BET specific surface area of ~ 39.18 m2 g−1. Adsorption experiments are carried out for the different values of pH of the solutions, contact time, and initial concentration of metal ions. High efficiency Cr6+, Cd2+, and Pb2+ removal occur at pH 3, 7, and 5.5, respectively. Equilibrium study reveals that the heavy metal ion adsorption of the α-Fe2O3 nanocrystals followed Langmuir and Freundlich isotherm models. The Cr6+, Cd2+, and Pb2+ adsorption equilibrium data are best fitted to the Langmuir model. The maximum adsorption capacities of α-Fe2O3 nanocrystals related to Cr6+, Cd2+, and Pb2+ are found to be 15.15, 11.63, and 20 mg g−1, respectively. These results clearly suggest that the synthesized α-Fe2O3 nanocrystals can be considered as potential nano-adsorbents for future environmental and health related applications.
        4,000원
        27.
        2019.04 구독 인증기관·개인회원 무료
        To identify and compare the venom components and expression patterns of some bees/wasps, venom gland-specific transcriptome analyses were conducted for 14 Aculeate bees/wasps. Most of the allergens and pain-producing factors showed extremely high expression levels in social wasps, implying that social wasps have evolved to use venom to defend the colony against intruders. Acid phosphatase and tachykinin, which are known as allergens and neurotoxic peptides, were found with high frequencies in the venom glands of solitary wasps. This suggests that solitary wasps might use their venom for catching and preserving prey. In the venom glands of bumblebees, little or no transcripts of major allergens or pain producing factors were identified, implying that bumblebees venoms are relatively less toxic than those of social or solitary wasps. Taken together, the differential expression patterns of venom genes in some Aculeate bees/wasps implies that bees/wasps have unique groups of highly expressed venom components, which appear to have evolved in response to both ecological and behavioral influences.
        28.
        2018.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We report the structural, morphological and magnetic properties of the Ni70Mn30 alloy prepared by Planetary Ball Mill method. Keeping the milling time constant for 30 h, the effect of different ball milling speeds on the synthesis and magnetic properties of the samples was thoroughly investigated. A remarkable variation in the morphology and average particle size was observed with the increase in milling speed. For the samples ball milled at 200 and 300 rpm, the average particle size and hence magnetization were decreased due to the increased lattice strain, distortion and surface effects which became prominent due to the increase in the thickness of the outer magnetically dead layer. For the samples ball milled at 400, 500 and 600 rpm however, the average particle size and hence magnetization were increased. This increased magnetization was attributed to the reduced surface area to volume ratio that ultimately led to the enhanced ferromagnetic interactions. The maximum saturation magnetization (75 emu/g at 1 T applied field) observed for the sample ball milled at 600 rpm and the low value of coercivity makes this material useful as soft magnetic material.
        4,000원
        29.
        2018.10 구독 인증기관·개인회원 무료
        To identify the venom components and their expression patterns of some Aculeata bees/wasps, venom gland-specific transcriptome analysis was conducted. FPKM values were normalized with the average of the transcription level of reference gene (a-tubulin). Common components in both solitary and social wasp venoms include hyaluronidase, phospholipase A2, metalloendopeptidase, etc. Although it has been expected that more diverse bioactive components with the functions of prey inactivation and physiology manipulation are present in solitary wasps, the information on venom compositions of solitary wasps obtained in this study was not sufficient to generalizae this notion. Nevertheless, some neurotoxic peptides (e.g., pompilidotoxin and dendrotoxin-like peptide) and proteins (e.g., insuline-like peptide binding protein) appear to be specific to solitary wasp venom. In contrast, several proteins, such as venom allergen 5 protein, venom acid phosphatase, and various phospholipases, appear to be relatively more abundant in social wasp venom. In the venom gland trancsriptome of bumblebees, major allergens or pain producing factors were barely identified, implying that bumblebee venoms are relatively less toxic than those of social or solitary wasps.
        30.
        2018.04 구독 인증기관·개인회원 무료
        The common bed bug, Cimex lectularius, possesses a cholinesterase expressed exclusively in the salivary gland (ClSChE). In this paper, we investigated the molecular structure, tissue distribution patterns, and biochemical properties of ClSChE and showed that ClSChE exists as a soluble monomeric form or a soluble dimeric form connected by a disulfide bridge. Immunohistochemical analysis confirmed that ClSChE was expressed in the epithelial cells of both the salivary gland and the duct. In addition, the secretion of monomeric ClSChE through the proboscis during feeding was detected by western blotting using a ClSChE-specific antibody. To predict the role of ClSChE injected into the tissue of an animal host, we analyzed the extent of sequestration and hydrolysis of acetylcholine (ACh)/choline (Ch) by ClSChE by ultra-performance liquid chromatography-tandem mass spectrometry. Kinetic analysis revealed that ClSChE possesses extremely low Km (high affinity to ACh) and Vmax values. These findings suggest that ClSChE functions as a sequestering enzyme specific to ACh (not to Ch) by having a very strong affinity to ACh but an extremely long turnover time.
        31.
        2017.10 구독 인증기관·개인회원 무료
        The members of the genus Flavivirus are noteworthy, as they cause infectious diseases in humans, such as Zika, denguefever, yellow fever, West Nile, and Japanese encephalitis. Due to the increased awareness of the public health risk posedby flavivirus-infected mosquitoes, mosquito collections were performed in six urban parks of South Korea, as the parksare designated for human recreation but also provide suitable habitats for mosquitoes. We examined the diversity andabundance of mosquito species and conducted molecular diagnostics for the detection of flavivirus infections. Monthlycollections were carried out in each park from March to August in 2017. A total of 4,851 mosquitoes (5 genera and13 species) were collected using BG-sentinel traps and then investigated for flavivirus infections. Pathogenic flavivirusinfections causing human diseases were not observed in the field-collected mosquitoes. However, insect-specific flavivirus(ISF) infections were detected in several mosquito pools. ISF has been previously known to enhance or suppress the replicationof medically important flaviviruses in co-infected mosquito cells. In this study, partial sequences of ISF were analyzed.However, further studies are needed in order to determine its genetic characterization and biological function in vivo.
        32.
        2017.06 구독 인증기관 무료, 개인회원 유료
        Selecting an appropriate antigen with optimal immunogenicity and physicochemical properties is a pivotal factor to develop a protein based subunit vaccine. Despite rapid progress in modern molecular cloning and recombinant protein technology, there remains a huge challenge for purifying and using protein antigens rich in hydrophobic domains, such as membrane associated proteins. To overcome current limitations using hydrophobic proteins as vaccine antigens, we adopted in silico analyses which included bioinformatic prediction and sequence-based protein 3D structure modeling, to develop a novel periodontitis subunit vaccine against the outer membrane protein FomA of Fusobacterium nucleatum. To generate an optimal antigen candidate, we predicted hydrophilicity and B cell epitope parameter by querying to web-based databases, and designed a truncated FomA (tFomA) candidate with better solubility and preserved B cell epitopes. The truncated recombinant protein was engineered to expose epitopes on the surface through simulating amino acid sequence-based 3D folding in aqueous environment. The recombinant tFomA was further expressed and purified, and its immunological properties were evaluated. In the mice intranasal vaccination study, tFomA significantly induced antigen-specific IgG and sIgA responses in both systemic and oral-mucosal compartments, respectively. Our results testify that intelligent in silico designing of antigens provide amenable vaccine epitopes from hard-to-manufacture hydrophobic domain rich microbial antigens.
        4,000원
        33.
        2017.04 구독 인증기관·개인회원 무료
        Aedes albopictus is one species of mosquito transmitting flavivirus causing Dengue, Zika, and West Nile fever. Although it is an important disease vector, the genetic study of Ae. alpopictus populations has not been undertaken yet in South Korea. Here, we investigated the genetic variation of 99 Ae. albopictus individuals collected from 29 sites in nine provinces in 2016, through mitochondrial COI gene analysis. Haplotype analyses revealed seven haplogroups in South Korea. The main haplogroup, comprising 76 individuals (77.8%), was genetically identical to the one from Nagasaki. Two groups from Jeju Island (11) and the southern coast of South Korea (nine) were closely related to different Ae. albopictus strains from Kumamoto and Guangdong/Fujian, respectively. However, the others (four) were distinct from these two countries. No geographic divisions of populations were found in the study regions. The results suggest the possibility that the currently prevalent Ae. albopictus in South Korea, represents a part of the descendants that originated from nearby countries. However, more comprehensive investigations are needed to explain its movement routes.
        34.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated multidimensional body image, self-esteem, clothing benefits sought, and Body Image After Breast Cancer (BIABC) within surgical subgroups among breast cancer survivors. The study applied the questionnaire survey method and the main research was conducted through an online survey. The respondents included 207 breast cancer survivors between the ages of 30 and 59, each of whom received the Multidimensional Body-Self Relations Questionnaire (MBSRQ). Self-esteem, clothing benefits sought, examination, and demographic variables were measured using a 5-point Likert scale. The main results of this study are outlined below. For clothing benefit sought, six factors were formulated—pursuit of self-expression/social approval, function/health, compensation, femininity, fashion, and camouflage—and BIABC was defined by the four factors of body stigma/vulnerability, transparency, limitation and cancer concern. While MBSRQ and self-esteem did not show a statistically significant difference between groups differentiated by the surgical methods experienced, those who underwent mastectomies scored slightly lower than members of the other groups. Moreover, the reconstruction after mastectomy group showed the highest mean on self-expression/social approval, compensation, femininity and entire clothing benefits sought, followed by the lumpectomy group and mastectomy group. The lumpectomy group was found to have more positive BIABC than the mastectomy group. In particular, the mastectomy group showed a lower body stigma/vulnerability mean than the other groups. This study is meaningful in that it improves our understanding of the body image of breast cancer survivors and provides basic knowledge for developing products and marketing strategies for breast cancer survivors as consumers.
        5,100원
        39.
        2016.04 구독 인증기관·개인회원 무료
        Brachymystax lenok tsinlingensis (family Salmonidae), cold freshwater fish, is endemic to Asia. This species is currently distributed throughout Russia, Mongolia, China and the Korean Peninsula. B. lenok tsinlingensis in South Korea was severely affected by anthropogenic activities such as habitat destruction, agricultural run-off and water pollution, and hence this fish has recently been dramatically decreased in its population sizes and become now critically endangered. To recover the number of individuals of B. lenok tsinlingensis, stocking or translocation programs have been conducted continuously by local governments since 1970s. However, these programs made little effort to clarify populations that may have originated from stocked, translocated or introduced fish. An understanding of genetic characteristics of endangered populations is critical to develop effective conservation and restoration plans especially because genetic diversity ensues their future fate. Therefore, we assessed the “conservation status” of this species by estimating the level of genetic diversity and genetic structure among ten geographic populations including restored populations via reinforcement and supplementation. Also, we aimed to trace the genetic origins of the newly translocated population (Chiak) through a restoration practice program. Moreover, we inferred the phylogenetic relationships among Korean lenok populations as well as across the Northeast Asia. Two hundred eighteen individuals of B. lenok tsinlingensis were sampled from ten localities (Yanggu, Injae, Seorak, Bangtae and Hongcheon: North Han River basin; Pyeongchang, Chiak and Jeongseon: South Han River basin; Taebaek and Bonghwa: Nakdong River basin in South Korea). Based on mitochondrial DNA (mtDNA) control region and eight nuclear microsatellite loci, we found extremely low levels of within-population genetic diversity, which suggests small effective population sizes (Ne) within populations. For mtDNA control region, each population housed one, or at most, two haplotypes that are restricted to the respective localities, meaning that these ‘genetically unique’ lineages will be lost permanently if the local populations undergo extinction. The overall values of haplotype diversity (h) and nucleotide diversity (π) for the entire Korean population were 0.703 ± 0.024 and 0.021 ± 0.010, respectively. In the case of microsatellites, average number of alleles across the eight loci for the entire population was 9.1 and allelic richness (AR) per population ranged from 2.375 to 4.144 (mean = 3.104). The values of observed heterozygosity (HO) and expected heterozygosity (HE) were similar to each other [HO: 0.400 ~ 0.590 (mean = 0.518); HE: 0.407 ~ 0.608 (mean = 0.504)]. The inbreeding coefficient (FIS) values were generally low, ranging from 0.048 to 0.279. Consequently, the majority of the populations (except Yanggu and Pyeongchang) were not significantly deviated from Hardy-Weinberg equilibrium (HWE), suggesting random mating at these loci tested. In addition, we found that Korean lenok populations were significantly genetically isolated from each other, with private mtDNA haplotypes and microsatellite alleles, indicating limited gene flow among populations, strong effects of genetic drift due to small Ne, or a combination of both. The Mantel test of microsatellites revealed a significant correlation (r = 0.414, P = 0.04) between genetic and geographic distances for pairwise comparisons among the ten populations, while that of mtDNA showed a lack of correlation. Given the shared identical mtDNA haplotype and similar microsatellite allelic distributions between Chiak and Hongcheon populations, we suggest that the restored (introduced) Chiak population would be inferred to be genetically originated from Hongcheon population. Phylogenetic relationships among Northeast Asian populations showed that South Korean lineages have more recently diverged from China (Yellow River), than between North Korea and Russia. Although the phylogenetic relationship would be expected to be associated with geography, South-North Korea and China populations with a similar latitude was more phylogenetically closely related. These findings may suggest a possible scenario for the historical movements of B. lenok tsinlingensis in Northeast Asia during Last Glacial Maximum (LGM). It would be supported by the line of evidence that most lenok populations migrated to southward from Northern Asia such as Russia and Mongolia during LGM because the Korean Peninsula was landlocked as inland epoch and functioned as a southern shelter with Yellow River. For this reason, the Korean Peninsula is suggested to be an important geographical region for better understanding phylogenetic relationships and evolutionary histories of B. lenok tsinlingensis across the Northeast Asia. Despite large efforts made to develop several restoration programs in South Korea for B. lenok tsinlingensis, it is still unknown whether these past restoration efforts were successful or fruitless, mainly because of little attention paid to post-restoration monitoring research. Hence, there was a lack of their published official records. In the future, conservation and restoration projects of the Korean lenok populations should consider the genetic data for a better understanding of their ecological and evolutionary trajectories. And finally, we hope that our findings here can help inform on the future effective conservation and restoration plans for B. lenok tsinlingensis populatio ns in South Korea.
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