Synthesis of Carbon Nanotube-CuxO(x = 8, 64) Nanocrystal Composites

Yongqing Wu,추지준,Hyung-Kook Kim,Yoon-Hwae Hwang,Yongqing Wu,Zhenxia Wang,Se-Jeong Park 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.56 No.1

A simple, rapid and eco-friendly method has been introduced to prepare suboxide CuxO(x = 8, 64)nanocrystals on multiwall carbon nanotube (MWCNT) composites. The structural characterization by using high-resolution transmission electron microscopy and X-ray diffraction methods indicates that CuxO(x = 8, 64) can be uniformly grown on the sidewalls of carbon nanotube under direct copper deposition at room temperature. Our results suggest that the growth method of nano-CuxO (x = 8, 64) crystals could be used to synthesize other nano-metal suboxides, such as MxO [M=metal;x = 1, 2, 4, 8 and 64]

Open source board based acoustofluidic transwells for reversible disruption of the blood–brain barrier for therapeutic delivery

Ke Wang,Chao Sun,Povilas Dumčius,Hongxin Zhang,Hanlin Liao,Zhenlin Wu,Liangfei Tian,Wang Peng,Yongqing Fu,Jun Wei,Meng Cai,Yi Zhong,Xiaoyu Li,Xin Yang,Min Cui 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Background Blood–brain barrier (BBB) is a crucial but dynamic structure that functions as a gatekeeper for the central nervous system (CNS). Managing sufficient substances across the BBB is a major challenge, especially in the development of therapeutics for CNS disorders. Methods To achieve an efficient, fast and safe strategy for BBB opening, an acoustofluidic transwell (AFT) was developed for reversible disruption of the BBB. The proposed AFT was consisted of a transwell insert where the BBB model was established, and a surface acoustic wave (SAW) transducer realized using open-source electronics based on printed circuit board techniques. Results In the AFT device, the SAW produced acousto-mechanical stimulations to the BBB model resulting in decreased transendothelial electrical resistance in a dose dependent manner, indicating the disruption of the BBB. Moreover, SAW stimulation enhanced transendothelial permeability to sodium fluorescein and FITC-dextran with various molecular weight in the AFT device. Further study indicated BBB opening was mainly attributed to the apparent stretching of intercellular spaces. An in vivo study using a zebrafish model demonstrated SAW exposure promoted penetration of sodium fluorescein to the CNS. Conclusions In summary, AFT effectively disrupts the BBB under the SAW stimulation, which is promising as a new drug delivery methodology for neurodegenerative diseases.

Ginseng polysaccharides: A potential neuroprotective agent

Na Wang,Xianlei Wang,Mengjiao He,Wenxiu Zheng,Dongmei Qi,Yongqing Zhang,Chun-chao Han 고려인삼학회 2021 Journal of Ginseng Research Vol.45 No.2

The treatments of nervous system diseases (NSDs) have long been difficult issues for researchers because of their complexity of pathogenesis. With the advent of aging society, searching for effective treatments of NSDs has become a hot topic. Ginseng polysaccharides (GP), as the main biologically active substance in ginseng, has various biological properties in immune-regulation, anti-oxidant, anti-inflammation and etc. Considering the association between the effects of GP and the pathogenesis of neurological disorders, many related experiments have been conducted in recent years. In this paper, we reviewed previous studies about the effects and mechanisms of GP on diseases related to nervous system. We found GP play an ameliorative role on NSDs through the regulation of immune system, inflammatory response, oxidative damage and signaling pathway. Structure-activity relationship was also discussed and summarized. In addition, we provided new insights into GP as promising neuroprotective agent for its further development and utilization.

Identification and functional prediction of long noncoding RNAs related to intramuscular fat content in Laiwu pigs

Wang Lixue,Xie Yuhuai,Chen Wei,Zhang Yu,Zeng Yongqing 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.1

Objective: Intramuscular fat (IMF) is a critical economic indicator of pork quality. Studies on IMF among different pig breeds have been performed via high-throughput sequencing, but comparisons within the same pig breed remain unreported. Methods: This study was performed to explore the gene profile and identify candidate long noncoding RNA (lncRNAs) and mRNAs associated with IMF deposition among Laiwu pigs with different IMF contents. Based on the longissimus dorsi muscle IMF content, eight pigs from the same breed and management were selected and divided into two groups: a high IMF (>12%, H) and low IMF group (<5%, L). Whole-transcriptome sequencing was performed to explore the differentially expressed (DE) genes between these two groups. Results: The IMF content varied greatly among Laiwu pig individuals (2.17% to 13.93%). Seventeen DE lncRNAs (11 upregulated and 6 downregulated) and 180 mRNAs (112 upregulated and 68 downregulated) were found. Gene Ontology analysis indicated that the following biological processes played an important role in IMF deposition: fatty acid and lipid biosynthetic processes; the extracellular signal-regulated kinase cascade; and white fat cell differentiation. In addition, the peroxisome proliferator-activated receptor, phosphatidylinositol- 3-kinase-protein kinase B, and mammalian target of rapamycin pathways were enriched in the pathway analysis. Intersection analysis of the target genes of DE lncRNAs and mRNAs revealed seven candidate genes associated with IMF accumulation. Five DE lncRNAs and 20 DE mRNAs based on the pig quantitative trait locus database were identified and shown to be related to fat deposition. The expression of five DE lncRNAs and mRNAs was verified by quantitative real time polymerase chain reaction (qRT-PCR). The results of qRT-PCR and RNA-sequencing were consistent. Conclusion: These results demonstrated that the different IMF contents among pig individuals may be due to the DE lncRNAs and mRNAs associated with lipid droplets and fat deposition. Objective: Intramuscular fat (IMF) is a critical economic indicator of pork quality. Studies on IMF among different pig breeds have been performed via high-throughput sequencing, but comparisons within the same pig breed remain unreported.Methods: This study was performed to explore the gene profile and identify candidate long noncoding RNA (lncRNAs) and mRNAs associated with IMF deposition among Laiwu pigs with different IMF contents. Based on the longissimus dorsi muscle IMF content, eight pigs from the same breed and management were selected and divided into two groups: a high IMF (>12%, H) and low IMF group (<5%, L). Whole-transcriptome sequencing was performed to explore the differentially expressed (DE) genes between these two groups.Results: The IMF content varied greatly among Laiwu pig individuals (2.17% to 13.93%). Seventeen DE lncRNAs (11 upregulated and 6 downregulated) and 180 mRNAs (112 upregulated and 68 downregulated) were found. Gene Ontology analysis indicated that the following biological processes played an important role in IMF deposition: fatty acid and lipid biosynthetic processes; the extracellular signal-regulated kinase cascade; and white fat cell differentiation. In addition, the peroxisome proliferator-activated receptor, phosphatidylinositol-3-kinase-protein kinase B, and mammalian target of rapamycin pathways were enriched in the pathway analysis. Intersection analysis of the target genes of DE lncRNAs and mRNAs revealed seven candidate genes associated with IMF accumulation. Five DE lncRNAs and 20 DE mRNAs based on the pig quantitative trait locus database were identified and shown to be related to fat deposition. The expression of five DE lncRNAs and mRNAs was verified by quantitative real time polymerase chain reaction (qRT-PCR). The results of qRT-PCR and RNA-sequencing were consistent.Conclusion: These results demonstrated that the different IMF contents among pig individuals may be due to the DE lncRNAs and mRNAs associated with lipid droplets and fat deposition.

The role of long noncoding RNAs in livestock adipose tissue deposition - A review

Wang, Lixue,Xie, Yuhuai,Chen, Wei,Zhang, Yu,Zeng, Yongqing Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.7

With the development of sequencing technology, numerous, long noncoding RNAs (lncRNAs) have been discovered and annotated. Increasing evidence has shown that lncRNAs play an essential role in regulating many biological and pathological processes, especially in cancer. However, there have been few studies on the roles of lncRNAs in livestock production. In animal products, meat quality and lean percentage are vital economic traits closely related to adipose tissue deposition. However, adipose tissue accumulation is also a pivotal contributor to obesity, diabetes, atherosclerosis, and many other diseases, as demonstrated by human studies. In livestock production, the mechanism by which lncRNAs regulate adipose tissue deposition is still unclear. In addition, the phenomenon that different animal species have different adipose tissue accumulation abilities is not well understood. In this review, we summarize the characteristics of lncRNAs and their four functional archetypes and review the current knowledge about lncRNA functions in adipose tissue deposition in livestock species. This review could provide theoretical significance to explore the functional mechanisms of lncRNAs in adipose tissue accumulation in animals.

Graphene Oxide Nanosheet-Composited Poly(N-isopropylacrylamide) Hydrogel for Cell Sheet Recovery

Yongqing Xia,Han Wu,Dachao Tang,Shuai Gao,Binghe Chen,Zhujun Zeng,Shengjie Wang,Meiwen Cao,Dongxiang Li 한국고분자학회 2019 Macromolecular Research Vol.27 No.7

Cell sheet engineering technique has been applied to treat various tissues without the use of a traditional scaffold. To date, methods for the cell sheet harvesting depend mostly on grafted poly(N-isopropylacrylamide) (pNIPAAm) thin layers, while the native pNIPAAm hydrogel, which possibly presents the easiest way to prepare thermo-responsive materials, is not suitable for the cell sheet harvesting due to its low cell attachment. In this study, the graphene oxide (GO) nanosheet was utilized as an additive to enhance the bio-compatibility of the pNIPAAm hydrogel. Different concentrations of GO nanosheets were added to prepare GO/pNIPAAm composite hydrogels through the in-situ free radical polymerization with polyethylene glycol dimethacrylate (PEGDA) as a cross-linker. The results indicated that the physical properties of the composite hydrogels had little difference with that of the native pNIPAAm hydrogel. However, the cell attachment, proliferation and detachment behaviors on the composite hydrogel surface were greatly enhanced. Monkey fibroblast COS7 cells attached and proliferated better on the GO/pNIPAAm composite hydrogel, while intact COS7 cell sheets could be harvested from the composite hydrogels by simply lowering the temperature. In contrast, the cells appeared as clusters on the native pNIPAAm hydrogel. Furthermore, when HeLa and COS7 cells were seeded successively onto the micropatterned GO/pNIPAAm hydrogel, there could be the formation of a patterned HeLa/COS7 cell layer. The geometrically patterned GO/pNIPAAm hydrogel may provide an easy-to-prepare material for releasing patterned cell sheets compared to the specific cell-adhesive proteins reported to make patterned cell layers.

Improving Mycoplasma ovipneumoniae culture medium by a comparative transcriptome method

Xiaohui Wang,Wenguang Zhang,Yongqing Hao 대한수의학회 2020 Journal of Veterinary Science Vol.21 No.2

Mycoplasma ovipneumoniae (Mo) is difficult to culture, resulting in many difficulties in related research and application. Since nucleotide metabolism is a basic metabolism affects growth, this study conducted a “point-to-point” comparison of the corresponding growth phases between the Mo NM151 strain and the Mycoplasma mycoides subsp. capri (Mmc) PG3 strain. The results showed that the largest difference in nucleotide metabolism was found in the stationary phase. Nucleotide synthesis in PG3 was mostly de novo, while nucleotide synthesis in NM151 was primarily based on salvage synthesis. Compared with PG3, the missing reactions of NM151 referred to the synthesis of deoxythymine monophosphate. We proposed and validated a culture medium with added serine to fill this gap and prolong the stationary phase of NM151. This solved the problem of the fast death of Mo, which is significant for related research and application.

Incentive Mechanism based on Game Theory in Kad Network

왕서(Xu Wang),니영청(YongQing Ni),양대헌(DaeHun Nyang) 한국정보보호학회 2010 정보보호학회논문지 Vol.20 No.3

Kad 네트워크는 파일 공유 시스템 중 가장 널리 알려진 네트워크이다. 파일 공유 시스템은 사용자의 일방적 파일 다운로드 받기, 가짜파일 업로드하기, 바이러스 배포하기 등에 사용 되는 등의 문제를 가지고 있고, 이러한 문제점을 극복하기 위하여, 이 논문에서는 게임 이론을 바탕으로 하는 인센티브 메커니즘을 제안한다. 이 메커니즘은 Kad 사용자를 위하여 보다 안정적이고 효율적인 네트워크 환경을 만들어 준다. 즉, 쓸모 없고 위험한 파일 등을 제공하는 다른 사용자들이 처벌받는 것에 반하여, 가치 있는 리소스를 공유한 사용자는 신용이 증가하는 대가를 받는다. Kad 네트워크에서 이 인센티브 메커니즘은 사용자의 악의적인 행동을 찾거나 방지하고 사용자들 사이에서의 정직한 통신을 장려하는데 도움을 준다. The Kad network is a peer-to-peer (P2P) network which implements the Kademlia P2P overlay protocol. Nowadays, the Kad network has attracted wide concern as a popular architecture for file sharing systems. Meanwhile, many problems have been coming out in these file sharing systems such as freeriding of users, uploading fake files, spreading viruses, and so on. In order to overcome these problems, we propose an incentive mechanism based on game theory, it establishes a more stable and efficient network environment for Kad users. Users who share valuable resources receive rewards by increasing their credits, while others who supply useless or harmful files are punished. This incentive mechanism in Kad network can be used to detect and prevent malicious behaviors of users and encourage honest interaction among users.

Application of the Multi-Source Data Fusion Algorithm in the Hail Identification

Yonghua Zhu,Yongqing Wang,Zhiqun Hu,Fansen Xu,Renqiang Liu 한국기상학회 2022 Asia-Pacific Journal of Atmospheric Sciences Vol.58 No.3

In this study, the canonical correlation analysis algorithm (CCA) is used to fuse the two-dimensional wind field retrieved from the single-Doppler weather radar, the three-dimensional wind field retrieved from the dual-Doppler weather radars, the observations from the ground automatic weather stations and the meteorological reanalysis data in three hail episodes (“0625” episode in Beijing, “0330” and “0801” episodes in Guangdong). During the hail episode in Beijing on June 25, 2020, an evident and long-lasting three-body scatter spike was observed, which played an important role in the hail identification and warning. In the three-dimensional wind field retrieved from the dual-Doppler weather radars, there is horizontal convergence of northeasterly and northwesterly winds and that of northwesterly and southeasterly winds in the low-level strong echo area, and there are obvious updrafts in the vertical wind field structure. Such a circulation configuration is favorable for the development and maintenance of hail storm. The multi-source data fusion of the wind fields can effectively improve the identification of the low-level convergence. The data fusion for the other two hail episodes (“0330” and “0801” episodes in Guangdong) yields the same conclusion. It is revealed that the dual-radar fusion performs better than the single-radar fusion in the identification of the meso-γ scale vortices. It can visually illustrate the characteristics of the cyclonic convergent flow fields which is more consistent with the near-surface observation. It can be concluded that the multi-source data fusion technique is practicable in the three severe convection processes.

A Comparative Study on the Effect of Upstream Trough on Intensity Changes of Two Types of Tropical Cyclones during Extratropical Transition

Yue Liao,Yongqing Wang,Jialing Zhou,Xiunian Zhang 한국기상학회 2020 Asia-Pacific Journal of Atmospheric Sciences Vol.56 No.1

Based on the China Meteorological Administration (CMA) tropical cyclone (TC) database and the reanalysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF), the post-transition intensifying tropical cyclones (ITC) and weakening tropical cyclones (WTC) which landed in China and underwent extratropical transition (ET) are discussed in this paper. The TCs with upper-level trough are selected in order to identify different effects of the trough on the ITC and the WTC. The dynamic composite analysis is applied to explore their structure characteristics, environment fields and dynamic diagnosis. Results show that affected by the South Asia high and the subtropical high, the trough of ITC (WTC) extends from northwest to southeast (northeast to southwest) in the ET process. Thus, the zonal wind shear of ITC drops off after ET due to the approach of trough and its northwestsoutheast direction, while the zonal and total wind shears of WTC continue to increase because of the steering westerly flow at the upper level. In terms of the ITC, the cold air carried by the upper-level trough intrudes into TC inner area and mostly encircles the TC center, making the ITC characterized by a warm seclusion. While for the WTC, the cold air only wanders on the northwest side of TC without further intrusion. The upper-level divergence is also in favor of the ITC by the pumping influence. According to the diagnostic analysis of moist potential vorticity, the moist baroclinity can lead to changes in vertical vorticity to some extent. The vertical vorticity budget analysis further indicates that there is stronger and wider positive vorticity advection in the upper troposphere near the TC center for ITC. The contribution of the baroclinic term to the growth of vertical vorticity is more significant in ITC than WTC but it is also deeply influenced by the strength of upper-level trough.