• 제목/요약/키워드: Delivery Systems

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Advances in Biodegradable Polymers for Drug Delivery Systems

  • Yong Kiel sung;Kim, Sung-Wan
    • Macromolecular Research
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    • 제8권5호
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    • pp.199-208
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    • 2000
  • The recent development of biodegradable polymers for drug delivery system (DDS) has been investigated. The biodegradable polymers for DDS are mainly discussed in two categories: one category is natural biodegradable polymers such as polysaccharides, modified celluloses, poly(${\alpha}$-amino acid)s, modified proteins, and microbial biodegradable polymers; the other is synthetic biodegradable polymers such as poly(ester)s, poly(ortho ester)s, poly(phosphazene)s, poly(anhydride)s, poly(alkyl cyanoacrylate)s, and multiblock copolymers. The bioconjugate polymeric drug delivery systems have been also proposed for the design of biocompatible polymeric controlled drug delivery.

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Hyaluronic Acid in Drug Delivery Systems

  • Jin, Yu-Jin;Ubonvan, Termsarasab;Kim, Dae-Duk
    • Journal of Pharmaceutical Investigation
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    • 제40권spc호
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    • pp.33-43
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    • 2010
  • Hyaluronic acid (HA) is a biodegradable, biocompatible, non-toxic, non-immunogenic and non-inflammatory linear polysaccharide, which has been used for various medical applications including arthritis treatment, wound healing, ocular surgery, and tissue augmentation. Because of its mucoadhesive property and safety, HA has received much attention as a tool for drug delivery system development. It has been used as a drug delivery carrier in both nonparenteral and parenteral routes. The nonparenteral application includes the ocular and nasal delivery systems. On the other hand, its use in parenteral systems has been considered important as in the case of sustained release formulation of protein drugs through subcutaneous injection. Particles and hydrogels by various methods using HA and HA derivatives as well as by conjugation with other polymer have been the focus of many studies. Furthermore, the affinity of HA to the CD44 receptor which is overexpressed in various tumor cells makes HA an important means of cancer targeted drug delivery. Current trends and development of HA as a tool for drug delivery will be outlined in this review.

Designing a Mobile Based Library Information and Service Delivery System: A Model Plan for Libraries of Bangladesh

  • Elahi, Md. Hasinul
    • Journal of Information Science Theory and Practice
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    • 제4권3호
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    • pp.57-70
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    • 2016
  • Purpose The purpose of the study is to identify the need of a mobile based library information and service delivery system in developing countries, identify the services that are possible to provide with the help of mobile phones and their applications, design a mobile based library information and service delivery system, and identify major challenges regarding mobile based library information and service delivery systems.Design/ Methodology/ Approach The research is exploratory in nature. This paper is based on a review of literature, survey information, and on the author’s own viewpoints. A comprehensive search of scientific literature has been done along with a survey for validating the necessity of designing mobile based library information and service delivery systems. Responses to closed-ended questions in particular on 7-point Likert scales were analyzed using the descriptive analysis techniques of SPSS 20.0 and responses to other closed-ended questions were analyzed using general statistics.Findings The research indicates that users of academic libraries, especially students and faculty members, have a positive notion regarding designing and implementing a mobile based library information and service delivery system. It also reveals user opinions regarding the possible problems associated with the design and implementation of a mobile based library information and service delivery system.Originality The paper explores mobile based library information and service delivery systems for better and faster service provision to its potential users.

Pollutant Delivery Ratio of Okdong-cheon Watershed Using HSPF Model (HSPF 모형을 이용한 옥동천 유역의 유달율 분석)

  • Lee, Hyunji;Kim, Kyeung;Song, Jung-Hun;Lee, Do Gil;Rhee, Han-pil;Kang, Moon Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • 제61권1호
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    • pp.9-20
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    • 2019
  • The primary objective of this study was to analyze the delivery ratio using Hydrological Simulation Program - Fortran (HSPF) in Okdong-cheon watershed. Model parameters related to hydrology and water quality were calibrated and validated by comparing model predictions with the 8-day interval filed data collected for ten years from the Korea Ministry of Environment. The results indicated that hydrology and water quality parameters appeared to be reasonably comparable to the field data. The pollutant delivery loads of the watershed in 2015 were simulated using the HSPF model. The delivery ratios of each subwatershed were also estimated by the simple ratio calculation of pollutant discharge load and pollutant delivery load. Coefficients of the regression equation between the delivery ratio and specific discharge were also computed using the delivery ratio. Based on the results, multiple regression analysis was performed using the discharge and the physical characteristics of the subwatershed such as the area. The equation of delivery ratio derived in this study is only for the Okdong-cheon watershed, so the larger studies are needed to apply the findings to other watersheds.

A Study of Consumers' Perceived Risk, Privacy Concern, Information Protection Policy, and Service Satisfaction in the Context of Parcel Delivery Services

  • Se Hun Lim;Jungyeon Sung;Daekil Kim;Dan J. Kim
    • Asia pacific journal of information systems
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    • 제27권3호
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    • pp.156-175
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    • 2017
  • The proposed conceptual framework is based in the relationships among knowledge of personal information security, trust on the personal information security policies of parcel delivery service companies, privacy concern, trust in and risk of parcel delivery services, and user satisfaction with parcel delivery services. Drawing upon both cognitive theory of emotion and cognitive emotion theory that complement each other, we propose a research model and examine the relationships between cognitive and emotional factors and the usage of parcel delivery services. The proposed model is validated using data from customers who have previously used parcel delivery services. The results show a significant relationship between the cognitive and affective factors and the usage of parcel delivery services. This study enhances our understanding of parcel delivery services based on the consumers' psychological processes and presents useful implications on the importance of privacy and security in these services.

Categorization of Regional Delivery System for the Elderly Chronic Health Care and Long-Term Care (지역별 노인 만성기 의료 및 요양·돌봄 공급체계 유형화)

  • Nan-He Yoon;Sunghun Yun;Dongmin Seo;Yoon Kim;Hongsoo Kim
    • Health Policy and Management
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    • 제33권4호
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    • pp.479-488
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    • 2023
  • Background: By applying the suggested criteria for needs-based chronic medical care and long-term care delivery system for the elderly, the current status of delivery system was identified and regional delivery systems were categorized according to quantity and quality of delivery system. Methods: National claims data were used for this study. All claims data of medical and long-term care uses by the elderly and all claims data from long-term care hospitals and nursing homes in 2016 were analyzed to categorize the regional medical and long-term care delivery system. The current status of the delivery system with a high possibility of transition to a needs-based appropriate delivery system was identified. The necessary and actual amount of regional supply was calculated based on their needs, and the structure of delivery systems was evaluated in terms of the needs-based quality of the system. Finally, all regions were categorized into 15 types of medical and care delivery systems for the elderly. Results: Of the total 55 regions, 89.1% of regions had an oversupply of elderly medical and care services compared to the necessary supply based on their needs. However, 69.1% of regions met the criteria for less than two types of needs groups, and 21.8% of regions were identified as regions where the numbers of institutions or regions with a high possibility of transition to an appropriate delivery system were below the average levels for all four needs groups. Conclusion: In order to establish an appropriate community-based integrated elderly care system, it is necessary to analyze the characteristics of the regional delivery system categories and to plan a needs-based delivery system regionally.

Synthesis and Characterization of HPMC Derivatives as Novel Duodenum-Specific Coating Agents

  • Huang Yuan;Zheng ling Ii;Liu Jun;Zhang Zhi rong
    • Archives of Pharmacal Research
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    • 제28권3호
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    • pp.364-369
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    • 2005
  • HPMC (Hydroxypropyl methylcellulose) was chemically modified, using maleic anhydrides, to obtain pH-sensitive HPMCAM (Hydroxypropyl methylcellulose acetate maleate) polymers for use as novel duodenum-specific coating agents. The pharmaceutical properties of HPMCAM, such as film forming, acid values, pH-sensitive values, water vapor permeability, tensile strength and Tg, were investigated, and found to show good film forming properties. The pH­sensitive values were 3.0 to 3.7. In vitro results demonstrate that HPMCAM could completely suppress drug release within 2h in a simulated gastric fluid (pH 1.2) and rapidly release the drug in a simulated pathological duodenal fluid (pH 3.4). These results indicate that HPMCAM might be a useful material for a duodenum-specific drug delivery system.

A Tradeoff between Customer Efficiency and Firm Productivity in Service Delivery Systems

  • Trinh, Truong Hong;Kachitvichyanukul, Voratas;Luong, Huynh Trung
    • Industrial Engineering and Management Systems
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    • 제11권3호
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    • pp.224-232
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    • 2012
  • The paper proposes a non-parametric methodology, data envelopment analysis, for measuring efficiency and productivity in service delivery systems with capacity constraints. The methodology provides allocation approaches for studying behaviors of firm and customers in service delivery strategy. The experimental study is carried out to investigate allocation behaviors and conduct an objective tradeoff between efficiency approach and productivity approach. The experimental result indicates that the efficiency approach allocates resource via maximizing customer efficiency rather than firm productivity as in the productivity approach. Moreover, the experiment reveals that there exists an objective tradeoff between the efficiency approach and the productivity approach. These findings provide strategic options for allocation policy in service delivery systems.

Development of Low Cost Autonomous-Driving Delivery Robot System Using SLAM Technology (SLAM 기술을 활용한 저가형 자율주행 배달 로봇 시스템 개발)

  • Donghoon Lee;Jehyun Park;Kyunghoon Jung
    • IEMEK Journal of Embedded Systems and Applications
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    • 제18권5호
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    • pp.249-257
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    • 2023
  • This paper discusses the increasing need for autonomous delivery robots due to the current growth in the delivery market, rising delivery fees, high costs of hiring delivery personnel, and the need for contactless services. Additionally, the cost of hardware and complex software systems required to build and operate autonomous delivery robots is high. To provide a low-cost alternative to this, this paper proposes a autonomous delivery robot platform using a low-cost sensor combination of 2D LIDAR, depth camera and tracking camera to replace the existing expensive 3D LIDAR. The proposed robot was developed using the RTAB-Map SLAM open source package for 2D mapping and overcomes the limitations of low-cost sensors by using the convex hull algorithm. The paper details the hardware and software configuration of the robot and presents the results of driving experiments. The proposed platform has significant potential for various industries, including the delivery and other industries.

Development and evaluation of probiotic delivery systems using the rennet-induced gelation of milk proteins

  • Ha, Ho-Kyung;Hong, Ji-Young;Ayu, Istifiani Lola;Lee, Mee-Ryung;Lee, Won-Jae
    • Journal of Animal Science and Technology
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    • 제63권5호
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    • pp.1182-1193
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    • 2021
  • The aims of this study were to develop a milk protein-based probiotic delivery system using a modified rennet-induced gelation method and to determine how the skim milk powder concentration level and pH, which can affect the rennet-induced intra- and inter-molecular association of milk proteins, affect the physicochemical properties of the probiotic delivery systems, such as the particle size, size distribution, encapsulation efficiency, and viability of probiotics in simulated gastrointestinal tract. To prepare a milk protein-based delivery system, skim milk powder was used as a source of milk proteins with various concentration levels from 3 to 10% (w/w) and rennet was added to skim milk solutions followed by adjustment of pH from 5.4 or 6.2. Lactobacillus rhamnosus GG was used as a probiotic culture. In confocal laser scanning microscopic images, globular particles with a size ranging from 10 ㎛ to 20 ㎛ were observed, indicating that milk protein-based probiotic delivery systems were successfully created. When the skim milk powder concentration was increased from 3 to 10% (w/w), the size of the delivery system was significantly (p < 0.05) increased from 27.5 to 44.4 ㎛, while a significant (p < 0.05) increase in size from 26.3 to 34.5 ㎛ was observed as the pH was increased from 5.4 to 6.4. An increase in skim milk powder concentration level and a decrease in pH led to a significant (p < 0.05) increase in the encapsulation efficiency of probiotics. The viability of probiotics in a simulated stomach condition was increased when probiotics were encapsulated in milk protein-based delivery systems. An increase in the skim milk powder concentration and a decrease in pH resulted in an increase in the viability of probiotics in simulated stomach conditions. It was concluded that the protein content by modulating skim milk powder concentration level and pH were the key manufacturing variables affecting the physicochemical properties of milk protein-based probiotic delivery systems.