Structural optimization of rapidly separating microneedles for efficient drug delivery

Dan Dan Zhu,Bo Zhi Chen,Meng Chan He,Xin Dong Guo 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.51 No.-

Rapidly separating microneedles (RSMNs) arose as an improvement of traditional MNs for the specialseparable structures. The aim of this study was to investigate various structural parameters contributedto the delivery performance of RSMNs. The experimental results indicated that the optimized RSMNswith 500 mm-long solid PLA MNs, 250 mm-long overlap and 500 mm-long dissolving MNs delivered over95% of drugs within 30 s. In the in vivo diabetic mice treatment, insulin loaded optimized RSMNs reachedapproximately the same therapeutic effect on lowering the glucose in blood as injection, significantlybetter than traditional MNs.

A Study on the Current Situation of the Social Mentality of Primary and Secondary School Teachers in China and the Corresponding Countermeasure

Guo, Dan Korean Society of Computer Information 2022 韓國컴퓨터情報學會論文誌 Vol.27 No.11

본 연구는 중국 안산시의 초중등학교 교사들의 "사회적 사고방식"을 연구하려는 시도가 이루어졌다. 연구를 진행하기 위해 안산시에 있는 298명 교사를 선정하여 설문조사를 실시하였다. 본 연구는 문헌조사와 설문조사를 결합한 방법을 채택하였다. 그 결과 안산시 초·중등학교 교사들의 전반적인 '사회심리학' 수준이 상대적으로 높은 것으로 나타났다. 교육 배경이 다른 교사의 직업 만족도에는 상당한 차이가 있습니다. 경로 모델은 변수 간의 상호 작용 메커니즘을 보여줍니다. 일반적인 자기 효능감과 업무 몰입도는 이 메커니즘에서 중요한 역할을 합니다.

Impact of Cu2O doping on high dielectric properties of CuO ceramics

Dan-Dan Wang,Feng-Zi Zhou,Jing-Xiao Cao,Li-Ben Li,Guo-Ling Li 한국물리학회 2017 Current Applied Physics Vol.17 No.5

Single-phase CuO ceramic samples were prepared with the starting nano powders of CuO þ xCu2O (x ¼ 0, 1, 3, 7% in mole ratio) via solid state reaction method, and characterized by X-ray diffraction, Raman scattering and scanning electron microscopy. For all the samples, the temperature dependences of dielectric constants and losses were measured at the frequencies of 102, 103, 104, 105 and 106 Hz, respectively. With increasing doping content of Cu2O, a strong correlation is demonstrated at given temperature and frequency between the measured dielectric constants and the unit-cell volumes of CuO. The strong correlation is argued in terms of the change in densities of Cu]O defects (e.g. Cu/O vacancies and/or interstitial Cu impurities) due to Cu2O doping, which is supported by the formation energies of Cu]O defects and the corresponding unit-cell volume from first-principles calculations. The high dielectric constant (~103e105) of CuO ceramic is therefore attributed to the reduction in resistance due to Cu/O defects in the grain by Maxwell-Wagner mechanism.

Privacy Protection in E-commerce : Identity-based Anonymous Privacy Agent

Dan Guo 보안공학연구지원센터 2014 International Journal of Security and Its Applicat Vol.8 No.3

Quality Evaluation of Five Commercial Enzyme Linked Immunosorbent Assay Kits for Detecting Aflatoxin B1 in Feedstuffs

Dan-dan Sun,Xu Gu,Jun-guo Li,Ting Yao,Ying-chao Dong 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.5

The objective of this study was to evaluate the quality of five commercial enzyme linked immunosorbent assay (ELISA) kits (A, B, C, D, and E) from different suppliers for detecting aflatoxin B1 (AFB1). AFB1-free corn samples supplemented with different levels of AFB1 (5, 10, and 20 μg/kg) were used as positive controls and 6 replicates of each control sample were tested to evaluate the accuracy and precision of these kits. In addition, we also evaluated the performance of these ELISA kits for AFB1 in 30 feed samples, including corn, distillers dried grains with soluble, wheat samples, soybean meal, and poultry feed, which were verified by high performance liquid chromatography. Results showed that the coefficients of variation ranged from 1.18% to 16.22% in intra-plate and 2.85% to 18.04% in inter-plate for the determination of AFB1. The half maximal inhibitory concentration for five kits ranged from 3.72 to 7.22 μg/kg. The quantitation limits of AFB1 were all under the legal limit in China but somewhat inconsistent with kit instructions. Although the recovery rate of four of the five kits were either less than 90% or more than 110%, all these values were acceptable in practice. Two kits had high false positive rates (C and E). In conclusion, our results revealed that the qualities of five tested ELISA kits were significantly different.

Human umbilical cord mesenchymal stem cells overexpressing RUNX1 promote tendon-bone healing by inhibiting osteolysis, enhancing osteogenesis and promoting angiogenesis

Guo Dan,Yang Jian,Liu Dianwei,Zhang Pei,Sun Hao,Wang Jingcheng 한국유전학회 2024 Genes & Genomics Vol.46 No.4

Background Rotator cuff injury (RCI) is a common shoulder injury, which is difficult to be completely repaired by surgery. Hence, new strategies are needed to promote the healing of tendon-bone. Objective We aimed to investigate the effect of human umbilical cord mesenchymal stem cells (hUC-MSCs) overexpressing RUNX1 on the tendon-bone healing after RCI, and to further explore its mechanism. Methods Lentiviral vector was used to mediate the overexpression of RUNX1. RUNX1-overexpressed UCB-MSCs (referred to as MSC-RUNX1) were co-cultured with osteoclasts, and TRAP staining was performed to observe the formation of osteoclasts. Then MSC-RUNX1 was cultured in osteogenic differentiation medium, Alizarin red staining was conducted to detect osteogenic differentiation. The expression of markers of osteogenesis and osteoclast was detected by RT-qPCR. EA. hy926 cells were co-cultured with MSC-RUNX1. Transwell assay was used to detect the migration, and the expression of angiogenesis related-genes VEGF and TGF-β was detected by RT-qPCR. The rat rotator cuff reconstruction model was established and MSCs were injected at the tendon-bone junction. Biomechanical test and micro-CT scanning were performed, and HE, Masson and Alcian Blue staining were used for histological evaluation of tendon-bone healing. TUNEL and PCNA immunofluorescence (IF) staining were performed to evaluate apoptosis and proliferation at the tendon-bone healing site. The levels of TNF-α, IL-6 and IL-8 in serum were detected by ELISA. The expression of CD31 and Endomucin that related to angiogenesis was detected by IF. Safranin O-fast and TRAP/CD40L immunohistochemical staining were used to assess the levels of osteoclasts and osteoblasts at the tendon-bone healing site. Results hUC-MSCs overexpressing RUNX1 inhibited osteoclast formation and promoted osteogenic differentiation. MSC-RUNX1 could promote the migration and tube formation of EA. hy926 cells, and up-regulate the levels of VEGF and TGF-β. Model mice treated with MSC-RUNX1 partially restored the biomechanical indexes. Treatment of MSC-RUNX1 obviously increased the bone density, accompanied by the formation of new bone. In vivo experiments showed that MSC-RUNX1 treatment could promote tendon-bone healing and inhibit inflammatory response in rats. MSC-RUNX1 treatment also promoted angiogenesis at the tendon-bone healing site, while inhibiting osteoclast formation and promoting osteogenic differentiation. Conclusion hUC-MSCs overexpressing RUNX1 can inhibit the formation of osteoclasts and differentiation of osteoblasts, promote angiogenesis and inhibit inflammation, thereby promoting tendon-bone healing after RCI. Background Rotator cuff injury (RCI) is a common shoulder injury, which is difficult to be completely repaired by surgery. Hence, new strategies are needed to promote the healing of tendon-bone. Objective We aimed to investigate the effect of human umbilical cord mesenchymal stem cells (hUC-MSCs) overexpressing RUNX1 on the tendon-bone healing after RCI, and to further explore its mechanism. Methods Lentiviral vector was used to mediate the overexpression of RUNX1. RUNX1-overexpressed UCB-MSCs (referred to as MSC-RUNX1) were co-cultured with osteoclasts, and TRAP staining was performed to observe the formation of osteoclasts. Then MSC-RUNX1 was cultured in osteogenic differentiation medium, Alizarin red staining was conducted to detect osteogenic differentiation. The expression of markers of osteogenesis and osteoclast was detected by RT-qPCR. EA. hy926 cells were co-cultured with MSC-RUNX1. Transwell assay was used to detect the migration, and the expression of angiogenesis related-genes VEGF and TGF-β was detected by RT-qPCR. The rat rotator cuff reconstruction model was established and MSCs were injected at the tendon-bone junction. Biomechanical test and micro-CT scanning were performed, and HE, Masson and Alcian Blue staining were used for histological evaluation of tendon-bone healing. TUNEL and PCNA immunofluorescence (IF) staining were performed to evaluate apoptosis and proliferation at the tendon-bone healing site. The levels of TNF-α, IL-6 and IL-8 in serum were detected by ELISA. The expression of CD31 and Endomucin that related to angiogenesis was detected by IF. Safranin O-fast and TRAP/CD40L immunohistochemical staining were used to assess the levels of osteoclasts and osteoblasts at the tendon-bone healing site. Results hUC-MSCs overexpressing RUNX1 inhibited osteoclast formation and promoted osteogenic differentiation. MSC-RUNX1 could promote the migration and tube formation of EA. hy926 cells, and up-regulate the levels of VEGF and TGF-β. Model mice treated with MSC-RUNX1 partially restored the biomechanical indexes. Treatment of MSC-RUNX1 obviously increased the bone density, accompanied by the formation of new bone. In vivo experiments showed that MSC-RUNX1 treatment could promote tendon-bone healing and inhibit inflammatory response in rats. MSC-RUNX1 treatment also promoted angiogenesis at the tendon-bone healing site, while inhibiting osteoclast formation and promoting osteogenic differentiation. Conclusion hUC-MSCs overexpressing RUNX1 can inhibit the formation of osteoclasts and differentiation of osteoblasts, promote angiogenesis and inhibit inflammation, thereby promoting tendon-bone healing after RCI.

Advancing AI Governance and Lawmaking in China -Insights and Strategies-

구오단양 ( Dan-yang Guo ) 한중사회과학학회 2024 한중사회과학연구 Vol.22 No.2

기술이 빠르게 발전하는 세계에서 인공지능(AI)은 경제적 및 사회적 진보의 핵심 동력이 되었다. 또한, AI기술의 급속한 발전은 산업의 운영방식을 변화시키고, 고용 패턴을 바꾸며, 일상생활 경험을 재구성하고 있다. 그러나 이러한 빠른 발전은 윤리적 문제, 데이터 보안, 개인정보보호 등 많은 도전과제를 제기하고 있다. 이러한 배경을 바탕으로, 본 논문은 중국의 인공지능 거버넌스 및 입법의 역동성을, 특히 서방국가들의 글로벌 추세에 비추어 검토한다. 또 중국 기업이 직면한 국제적 AI 규제 관행의 차이로 인한 고유한 도전과 영향을 다룬다. 본 논문은 구체적인 AI 솔루션과 포괄적인 윤리 원칙을 결합하는 조화된 입법 접근을 제시하였다. 윤리적 거버넌스의 필요성을 강조하며, AI 개발에서의 투명성과 책임성의 중요성을 제시하였다. 또한, 훈련 데이터 거버넌스의 복잡성을 다루고, 알고리즘 편향을 완화하기 위해 합성 데이터와 규제 샌드박스 사용과 같은 실질적 효용에 근거하여 실현가능한 전략을 제안하였다. 본 연구를 통해AI발전에 부합하고, 미래에 대비한 입법 제안을 통해 국제사회와 괘를 같이 할 것이라 본다. 5) In today’s rapidly evolving technological landscape, Artificial Intelligence (AI) stands out as a pivotal force propelling economic and societal advancements. The rapid evolution of AI technology is revolutionizing operational modalities across various sectors, altering employment patterns, and reshaping everyday life experiences. However, this accelerated development also introduces numerous challenges, including ethical concerns, data security, and privacy protection. Against this backdrop, this paper delves into the dynamics of AI governance and legislation in China, within the context of global trends, with a specific emphasis on those from Western nations. It examines the unique methods and challenges of current AI governance in China. The paper advocates for a unified legislative approach that integrates specific AI solutions with overarching ethical principles. It highlights the essential nature of ethical governance and emphasizes the critical importance of transparency and accountability in the development of AI. Concluding with a call for agile and forward-looking legislation, the paper underscores the necessity for a balanced framework in China that intertwines technological advancements in AI with societal and individual interests.

Quality Evaluation of Five Commercial Enzyme Linked Immunosorbent Assay Kits for Detecting Aflatoxin B₁ in Feedstuffs

Sun, Dan-Dan,Gu, Xu,Li, Jun-Guo,Yao, Ting,Dong, Ying-Chao Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.5

The objective of this study was to evaluate the quality of five commercial enzyme linked immunosorbent assay (ELISA) kits (A, B, C, D, and E) from different suppliers for detecting aflatoxin $B_1$ ($AFB_1$). $AFB_1$-free corn samples supplemented with different levels of $AFB_1$ (5, 10, and $20{\mu}g/kg$) were used as positive controls and 6 replicates of each control sample were tested to evaluate the accuracy and precision of these kits. In addition, we also evaluated the performance of these ELISA kits for $AFB_1$ in 30 feed samples, including corn, distillers dried grains with soluble, wheat samples, soybean meal, and poultry feed, which were verified by high performance liquid chromatography. Results showed that the coefficients of variation ranged from 1.18% to 16.22% in intra-plate and 2.85% to 18.04% in inter-plate for the determination of $AFB_1$. The half maximal inhibitory concentration for five kits ranged from 3.72 to $7.22{\mu}g/kg$. The quantitation limits of $AFB_1$ were all under the legal limit in China but somewhat inconsistent with kit instructions. Although the recovery rate of four of the five kits were either less than 90% or more than 110%, all these values were acceptable in practice. Two kits had high false positive rates (C and E). In conclusion, our results revealed that the qualities of five tested ELISA kits were significantly different.

Mathematical programming model of process plant safety layout using the equipment vulnerability index

Liping Guo,Zhirong Wang,Pinkun Guo,Jinghong Wang,Dan Zhao 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.4

Safety is the focus of attention in plant layout problems. Previous studies have often expressed safety as a cost of risk, that is, the cost of property losses that may occur in an accident. In this paper, the influence of uncertainty on the equipment vulnerability is quantitatively considered and a more reliable process plant layout is proposed. The equipment vulnerability index is used to evaluate the vulnerability level of the target equipment in case of an accident, which is applied to propose a mixed-integer nonlinear optimized process plant layout to minimize domino risk. In addition, a decision matrix is applied to determine whether the risk level of the optimized layout of the target equipment is acceptable. Damage probability and vulnerability are the basic inputs of this matrix. The proposed method was applied to a coal-water slurry gasification process and the results show that the layout obtained by the proposed model has better practical value than the current layout, reducing the domino risk by 53.2%. Meanwhile, the model can be used to identify critical equipment and select targeted safety measures during the production stage.

Lack of Association of the MDR1 C3435T Polymorphism with Susceptibility to Gastric Cancer and Peptic Ulcer: a Systemic Review and Meta-analysis

Wu, Dan-Dan,Zhang, Ji-Xiang,Li, Jiao,Dong, Wei-Guo Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Background: The multidrug resistance 1 gene (MDR1) C3435T polymorphism has been demonstrated to influence the P-glycoprotein (P-gp) activity level which is related to inflammation and carcinogenesis. This meta-analysis was performed to estimate the association between the MDR1 C3435T polymorphism and the risk of gastric cancer (GC) and peptic ulcer (PU). Materials and Methods: A literature search was conducted with PubMed, Embase and the Cochrane library up to November 2013. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. Data were analyzed using Review Manager (Version 5.2), and Stata package (version 12.0) for estimation of publication bias. Results: Six case-control studies were included, of which five were for GC and two for PU. Overall, no evidence was found for any association between the MDR1 C3435T polymorphism and the susceptibility to GC and PU. In the stratified analysis by H. pylori infection status, stage and histology classification of GC, and PU type, there was still no significant association between them. Conclusions: This meta-analysis suggested that the MDR1 C3435T polymorphism is not associated with susceptibility to GC and PU. Large and well-designed studies are warranted to validate our findings.