Currently, microrobots are receiving attention because of their small size and motility, which can be applied to minimal invasive therapy. Additionally, various microrobots using hydrogel with the ...characteristics of biocompatibility and biodegradability are also being developed. Among them, microrobots that swell and deswell in response to temperature changes caused by external near infrared (NIR) stimuli, focused ultrasound, and an alternating magnetic field, have been receiving a great amount of interest as drug carriers for therapeutic cell delivery. In this study, we propose a spring type medical microrobot that can be manipulated by an electromagnetic actuation (EMA) system and respond to an external stimulus (NIR). Additionally, we verified its feasibility with regard to targeting and drug delivery. There exist various methods of fabricating a spring type microrobot. In this study, we adopted a simple method that entails using a perfluoroalkoxy (PFA) microtube and a syringe pump. Moreover, we also used a hydrogel mixture composed of natural alginate, N-Isopropylacrylamide (NIPAM) for temperature responsiveness, and magnetic nanoparticles (MNPs) for electromagnetic control. Then, we fabricated a spring type alginate/NIPAM hydrogel-based soft microrobot. Additionally, we encapsulated doxorubicin (DOX) for tumor therapy in the microrobot. To verify the feasibility of the proposed spring type hydrogel-based soft microrobot’s targeting and drug delivery, we developed an EMA and NIR integrated system. Finally, we observed the swelling and deswelling of the soft microrobot under NIR stimulation and verified the EMA controlled targeting. Moreover, we implemented a control function to release the encapsulated anticancer drug (DOX) through the swelling and deswelling of the soft microrobot by NIR, and evaluated the feasibility of cancer cell therapy by controlling the release of the drug from the soft microrobot.
Thiopurine therapy, commonly used in autoimmune conditions, can be complicated by life-threatening leukopenia. This leukopenia is associated with genetic variation in TPMT (encoding thiopurine ...S-methyltransferase). Despite a lower frequency of TPMT mutations in Asians, the incidence of thiopurine-induced leukopenia is higher in Asians than in individuals of European descent. Here we performed an Immunochip-based 2-stage association study in 978 Korean subjects with Crohn's disease treated with thiopurines. We identified a nonsynonymous SNP in NUDT15 (encoding p.Arg139Cys) that was strongly associated with thiopurine-induced early leukopenia (odds ratio (OR) = 35.6; P(combined) = 4.88 × 10(-94)). In Koreans, this variant demonstrated sensitivity and specificity of 89.4% and 93.2%, respectively, for thiopurine-induced early leukopenia (in comparison to 12.1% and 97.6% for TPMT variants). Although rare, this SNP was also strongly associated with thiopurine-induced leukopenia in subjects with inflammatory bowel disease of European descent (OR = 9.50; P = 4.64 × 10(-4)). Thus, NUDT15 is a pharmacogenetic determinant for thiopurine-induced leukopenia in diverse populations.
As South Korea is expected to become a super-aged society by 2025, diligent efforts have been made to reduce the social burden by promoting a productive and healthy elderly lifestyle. Individuals are ...encouraged to prepare throughout their early lives and construct a healthy residential environment. As one of several alternatives home healthcare is using the Internet of Things - referred as ambient assisted living (AAL) - is drawing much attention. Although the individual technologies of healthcare and smart home have undergone rapid development, there has been little integration between the two. Moreover, many technological developments do not consider the actual lives of the elderly. To effectively respond to the aging problem, the two technologies should be integrated and applied to residential environments based on daily routines of the elderly. The purpose of this study is to suggest the future direction for healthcare in smart homes in South Korea. To achieve this goal, we first examined the possibility of embedding healthcare services into smart homes in a non-invasive manner. Second, in-depth interviews were conducted with elderly citizens and silver town operators to elucidate characteristics of the elderly, and a healthcare scenario was suggested that could be applied to each smart home room.
•Analysis of twisting tendency in speed mode of twisted string actuator (SM-TSA).•A new simple nonlinear analytical model of SM-TSA.•A nonlinearity compensation algorithm using nonlinear models of ...SM-TSA.•Proposed analytical model could follow more accurately twisting tendency in SM-TSA.•Compensated linear translatory motion of SM-TSA using proposed analytical model.
A twisted string actuator (TSA) is an effective method that can change the rotational motion of a motor into a linear motion, as well as control the speed and stiffness of the actuator. In particular, because the speed mode of the TSA (SM-TSA) can adjust the rotation–linear motion ratio by changing the diameter and length of the twisting shaft, it is a good to increase the usability of the TSA. However, the SM-TSA has a significant limitation in that it demonstrates a nonlinear translatory motion with respect to the constant rotational motion of the motor in terms of its operating principle. To solve this problem, a more accurate modeling method of the SM-TSA should be applied to predict the nonlinearity and compensate for the nonlinearity. Herein, we analyze the tendency of the twisted strings of the SM-TSA and propose a more precise modeling method of the nonlinear SM-TSA. In addition, a nonlinearity compensation algorithm using the proposed modeling of the SM-TSA is developed to linearize the nonlinear translatory motion. Through various experiments of the SM-TSA, we validated that the proposed model exhibits the nonlinearity of the SM-TSA more precisely when compared to the previous model. Additionally, we confirmed that the nonlinearity compensation algorithm using the proposed model can perform more accurate linearization of the translatory motion of the SM-TSA.
With the development of the information technology industry, including artificial intelligence (AI) platforms, a Hyperconnected-society has arrived. Smart-Home technologies and services are ...continuing to overcome early challenges and expanding our expectations for their capabilities to the expectation that they will change our daily lives. The purpose of this study is to examine the theoretical background and trends of Smart-Home development in residential spaces as a recent trend and to derive suggestions for resident-centred Smart-Home planning and development through a questionnaire survey. For this, we collected information on the smart technology (service) and item preferences of visitors to the Smart-Home Living-lab and prepared an evaluation of our findings. From this, a broader understanding of Smart-Home was derived by viewing our data through the lens of usability Our survey, which interrogated all age groups indicated a high preference for items associated with health care, and emergency and safety response items. Second. In particular, there was a high interest in daily health and body change management , yet, contrary to expectations, the preference for health-related services and items was in the more senior group. It is also notable that reference scores were high for items corresponding to automatic sensing, that is, services and items that respond to daily behavior. This research is meaningful as a basic study in specific smart space planning in that uses a practical experience and evaluation of Smart Home where new smart services and items have been implemented, but which have not yet become common. It is also expected to contribute to improving effectiveness and satisfaction by analysing the experience and usability of items and services associated with smart home technology.
Researches on the biomedical wireless microrobot are being actively carried out. In particular, compared with conventional catheter intervention, the wireless locomotive microrobot using an ...electromagnetic navigation system (ENS) can have many advantages in ischemic heart disease therapy. The ENSs generally use a uniform magnetic field and gradient magnetic field for the actuation of microrobots. However, because most ENSs require many coils, they have severe limitations, including a complex structure, large energy consumption, increased power supply, and large system volume. This paper proposes a new ENS for a 3-D locomotive microrobot using only four electromagnetic coils. The proposed ENS has a very simple structure, which consists of two circular coils and two saddle coils. The alignment and propulsion of the microrobot are determined by the generated magnetic field and gradient magnetic field from the four coils. This paper proposes a control algorithm and a gravity compensation for a 3-D locomotive microrobot and validates the performance of the microrobot using the proposed ENS. Finally, through a locomotion test of a blood vessel phantom, it was demonstrated that the microrobot can move to a target position in the phantom and deliver a drug to the target lesion.
Various types of actuation methods for microrobots have been proposed. Among the actuation methods, electromagnetic based actuation (EMA) has been considered a promising actuation mechanism. In this ...paper, a new EMA system for three-dimensional (3D) locomotion and drilling of the microrobot is proposed. The proposed system consists of four fixed coil pairs and one rotating coil pair. In detail, the coil system has three pairs of stationary Helmholtz coil, a pair of stationary Maxwell coil and a pair of rotating Maxwell coil. The Helmholtz coil pairs can magnetize and align the microrobot to the desired direction and the two pairs of Maxwell coil can generate the propulsion force of the microrobot. In addition, the Helmholtz coil pairs can rotate the microrobot about a desired axis. The rotation of the microrobot is a drilling action through an occlusion in a vessel. Through various experiments, the 3D locomotion and drilling of the microrobot by using the proposed EMA system are demonstrated. Compared with other EMA systems, the proposed system can provide the advantages of consecutive locomotion and drilling of the microrobot.
Korean Munsal combines three types of muntin units, creating diverse patterns that enhance the aesthetic of traditional architectural facades. The researcher mathematically reviewed the generation ...principles of Munsal patterns, developed algorithms in Grasshopper for recognizing the pattern as a matrix, and proposed a method of reproducing the recognition matrix of Munsal. The paper includes a detailed explanation using Geobukgyeopsal, that showcases a complex pattern stemming from three directional units. The focus lies on the horizontal, vertical, and diagonal muntin edges, rather than the connection nodes. The recognition matrix of Munsal provides a foundation for digital design applications, such as facades.
For 3-D locomotion and drilling of a microrobot, we proposed an electromagnetic actuation (EMA) system consisting of three pairs of stationary Helmholtz coils, a pair of stationary Maxwell coils, and ...a pair of rotating Maxwell coils in the previous research . However, this system could have limited medical applications because of the pair of rotational Maxwell coils. In this paper, we propose a new EMA system with three pairs of stationary Helmholtz coils, a pair of stationary Maxwell coils, and a new locomotive mechanism for the same 3-D locomotion and drilling of the microrobot as achieved by the previously proposed EMA system. For the performance evaluation of the proposed EMA system, we perform a 3-D locomotion and drilling test in a blood vessel phantom. In addition, the two EMA systems are compared to show that the newly proposed EMA system has 440% wider working space and 49% less power consumption than the previous EMA system.
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