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Metal-organic frameworks (MOFs) are a class of microporous materials that have been highlighted with fast and selective sorption of gas molecules; however, they are at least partially unstable in the scale-up process. Here, we report a rational shaping of MOFs in a scalable architecture of fiber sorbent. The long-standing stability challenge of MOFs was resolved by using stable metal oxide precursors that are subject to controlled surface oxide dissolution-growth chemistry during the Mg-based MOF synthesis. Highly uniform MOF crystals are synthesized along with the open-porous fiber sorbents networks, showing unprecedented cyclic CO2 capacities in both flue gas and direct air capture (DAC) conditions. The same chemistry enables an in situ flow synthesis of Mg-MOF fiber sorbents, providing a scalable pathway for MOF synthesis in an inert condition with minimal handling steps. This modular approach can serve both as a reaction stage for enhanced MOF fiber sorbent synthesis and as a "process-ready" separation device.

Acetaminophen (paracetamol, APAP) is a major component of Tylenol, Penzal Q, and Panpyrin, and is the most commonly used antipyretic analgesic in children. The conventional oral drug delivery systems of APAP are pills and tablets. However alternative drug delivery methods are desirable in case of pediatric or geriatric patients, especially for drugs like APAP that must be taken in large doses at once. Another requirement for a good drug delivery system is the rapid dissolution to ensure a rapid therapeutic action as pain reliever. In this study Acetaminophen (paracetamol, APAP) was encapsulated in a water-soluble polymer. After the preparation of the solid dispersion by encapsulating acetaminophen in polyvinylpyrrolidone, the resultant granules were used in three formulations: tablets, chewable tablets, and oral dissolving films (ODF). Solid dispersions and prepared formulations were evaluated by Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffractometer (XRD), and universal tensile machine (UTM), and the release behavior was compared. As a result, it was confirmed that the oral dissolving films can be taken easily because it has the advantages of both tablet and liquid dosage form accurate dosage, easy administration, easy swallowing, and fast bioavailability. Furthermore, the drug absorption rate can be effectively increased by changing the formulation.

Microporous materials have the potential to enable new low energy separation processes due to their superb textural properties and structural diversity, yet these materials are facing practical cha...

오늘날 컴퓨터 그래픽은 다양한 분야에 널리 활용되고 있다. 컴퓨터 그래픽에 있어 모델링은 기초적이며 필수적인 요소이다. 파라메트릭 모델링은 전통적인 모델링 방식을 기반으로 지오메트리 수치 및 오브젝트 관계를 정의하는 수식의 매개 변숫값을 조정하는 방식으로 모델링을 진행한다. 파라메트릭 모델링 방식은 다소 복잡하고 다양한 방법으로 응용 및 접근되는 방식을 사용하기에 체계적인 연구가 필요하다. 본 연구에서는 파라메트릭 모델링이 전통적인 방식을 기반으로 이루어지기에 2장에서는 전통적인 모델링 방식에 대하여 알아보고 3장에서는 파라메트릭 모델링의 여러 가지 방식에 대하여 연구하였다. 모델링의 전통적인 방식은 폴리곤, 넙스, 서브디비젼으로 나누어 각각 모델링의 특징에 대하여 알아보았다. 3장의 파라메트릭 모델링에서는 하나 및 다양한 파라메트릭 모델링 툴을 사용한 예로 구분하였다. 파라메트릭 모델링 방식 중에서 구부리기, 팽창, 기울기, 가늘게 만들기, 뒤틀기 등의 툴은 전통적인 모델링 방식에 변형을 가하는 방식을 사용한다는 것을 알았다. 변형이라는 방식 외에 복제는 기존의 모델링을 복제하여 다양한 응용방식을 사용한다. 균열이라는 파라메트릭 모델링 방식은 모델링에 균열이 생기도록 하여 파괴 및 융합되는 방식으로 오브젝를 표현하는 것을 알았다. 또한 다양한 파라메트릭 모델링을 사용하면 다양한 파라메트릭 방식 각각의 특성을 살리며 복합적으로 혼합된 파라메트릭 모델링만의 고유한 형태적 특성을 구현 할 수 있다.

Hydrogel is in the spotlight as a useful biomaterial in the field of drug delivery and tissue engineering due to its similar biological properties to a native extracellular matrix (ECM). Herein, we proposed a ternary hydrogel of gellan gum (GG), silk fibroin (SF), and chondroitin sulfate (CS) as a biomaterial for cartilage tissue engineering. The hydrogels were fabricated with a facile combination of the physical and chemical crosslinking method. The purpose of this study was to find the proper content of SF and GG for the ternary matrix and confirm the applicability of the hydrogel in vitro and in vivo. The chemical and mechanical properties were measured to confirm the suitability of the hydrogel for cartilage tissue engineering. The biocompatibility of the hydrogels was investigated by analyzing the cell morphology, adhesion, proliferation, migration, and growth of articular chondrocytes-laden hydrogels. The results showed that the higher proportion of GG enhanced the mechanical properties of the hydrogel but the groups with over 0.75% of GG exhibited gelling temperatures over 40 °C, which was a harsh condition for cell encapsulation. The 0.3% GG/3.7% SF/CS and 0.5% GG/3.5% SF/CS hydrogels were chosen for the in vitro study. The cells that were encapsulated in the hydrogels did not show any abnormalities and exhibited low cytotoxicity. The biochemical properties and gene expression of the encapsulated cells exhibited positive cell growth and expression of cartilage-specific ECM and genes in the 0.5% GG/3.5% SF/CS hydrogel. Overall, the study of the GG/SF/CS ternary hydrogel with an appropriate content showed that the combination of GG, SF, and CS can synergistically promote articular cartilage defect repair and has considerable potential for application as a biomaterial in cartilage tissue engineering., This research was supported by the International Research and Development Program of the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (NRF-2017K1A3A7A03089427) and by the bilateral cooperation Program of the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (NRF-2019K2A9A1A06098563).

In legged locomotion, the contact force between a robot and the ground plays a crucial role in balancing the robot. However, in quadrupedal robots, general whole-body controllers generate feed-forward force commands without considering the actual torque or force feedback. This paper presents a whole-body controller using the actual joint torque measured from a torque sensor, which enables the quadrupedal robot to demonstrate both dynamic locomotion and reaction to external disturbances. We compute external joint torque using the measured joint torque and the robot’s dynamics, and then we transform this to the moment of the center of mass (CoM). Using the computed CoM moment, the moment-based impedance controller distributes a feed-forward force corresponding to the desired moment of the CoM to stabilize the robot’s balance. Furthermore, to recover balance, the CoM motion is generated using capture point-based stepping control and zero moment point trajectory. The proposed whole-body controller was tested on a quadrupedal robot, named AiDIN-VI. Locomotive abilities on uneven terrains and slopes and in the presence of external disturbances are verified through experiments.