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Families of children with special health care needs (CSHCN) routinely struggle to find suitable childcare. These families value childcare capable of supporting their child's needs, known as inclusive care, that requires trustworthy staff trained to safely care for CSHCN.This study aimed to understand the training, experience, confidence, and perceived barriers to providing inclusive care for CSHCN from the perspective of childcare providers and directors. Childcare providers (n = 263) and directors (n = 418) responded to a statewide survey in Wisconsin in 2019.Results show that both childcare providers and directors perceive that the providers lack confidence in providing inclusive care. Lack of staffing, training, and expertise of childcare providers were the most frequently reported barriers to provide inclusive care.These findings confirm the need for additional education, training, resources, and research to create and maintain more inclusive childcare settings for CSHCN.

Background and Objectives Community Aging in Place, Advancing Better Living for Elders (CAPABLE) is an evidence-based intervention to promote aging in place. Although CAPABLE has been implemented in more than 40 community sites, wide variation in implementation exists. Guided by the Consolidated Framework for Implementation Research (CFIR), this study sought to determine key barriers and facilitators that may influence CAPABLE implementation with older adult and care partner dyads through an area agency on aging (AAA). Research Design and Methods A formative evaluation was completed using qualitative data from the pilot of a Hybrid Trial Type 1 study implementing CAPABLE in an AAA. Multiple sources of data were collected, including 2 focus groups, field notes, a tracking log, and meetings with CAPABLE interventionists. Data were analyzed using a framework method and validated through a negative case analysis approach in NVivo 12 Pro. Results Fourteen dyads enrolled in the pilot and 6 completed the CAPABLE intervention. Key themes aligned with 10 constructs from 5 domains of the CFIR. Facilitators included adaptability of the intervention, cost, networks and communication, and knowledge and belief of individuals. Barriers included intervention complexity, client needs and resources, and executing the planned process. Discussion and Implications Results enhance understanding of contextual factors that can influence the implementation of CAPABLE with care partners. Strategies to overcome barriers include simplifying recruitment materials and targeting older adults with recent onset of disability. The CFIR is a valuable resource for planning and evaluation of the implementation of evidence-based interventions to promote aging in place.

Phosphorescent and thermally activated delayed fluorescence (TADF) blue organic light-emitting diodes (OLEDs) have been developed to overcome the low efficiency of fluorescent OLEDs. However, device instability, originating from triplet excitons and polarons, limits blue OLED applications. Here, we develop a phosphor-sensitized TADF emission system with TADF emitters to achieve high efficiency and long operational lifetime. Peripheral carbazole moieties are introduced in conventional multi-resonance–type emitters containing one boron atom. The triplet exciton density of the TADF emitter is reduced by facilitating reverse intersystem crossing, and the Förster resonant energy transfer rate from phosphor sensitizer is enhanced by high absorption coefficient of the emitters. The emitter exhibited an operational lifetime of 72.9 hours with Commission Internationale de L’Eclairage chromaticity coordinate y = 0.165, which was 6.6 times longer than those of devices using conventional TADF emitters.

Mesenchymal stem-cell (MSC)-based therapies have been recognized as promising strategies for the treatment of various injuries or diseases because of their unique characteristics, such as self-renewal, differentiation potential, and secretion of various bioactive molecules. However, MSC transplantation often results in low efficacy, including a cell viability loss and a low therapeutic activity. Alternatively, MSC spheroids have been studied to improve the viability and therapeutic activity of MSCs. Also, microencapsulation of cells can protect and retain the cells from harsh environments after transplantation. Here, MSC spheroids were formed in hyaluronic acid/alginate (HA@Alg) core-shell microcapsules and employed for neovascularization. A well-defined core-shell structure of HA@Alg microcapsules was produced by optimizing various electrospraying conditions. MSC spheroids could be spontaneously formed in the HA core of the microcapsules after 1 day of incubation. Enhanced secretion of various growth factors was found from MSC spheroids in HA@Alg. In vivo plug assay revealed the significant promotion of angiogenesis by MSC spheroids in HA@Alg compared to that by the controls (i.e., MSCs and MSC spheroids), which is likely because of the better retention of MSC spheroid forms in the microcapsules. Thus, the HA@Alg microcapsules embedding MSC spheroids will be greatly beneficial for various stem cell-based therapies.

Background: Suicide is the leading cause of death among adolescents in South Korea. Negative influences of the abuse of energy drinks on mental health problems have emerged. Aims: This study aimed to analyze the relationship between energy drink consumption, depression and suicide ideation. Methods: We analyzed the data of 26,346 boys and 26,966 girls who participated in the 2015 Korean Youth Risk Behavior Web-Based Survey. The independent variable was the frequency of energy drink consumption per week. Experience of depression and suicide ideation were considered as the dependent variables. Multiple logistic regression was performed. Results: An association was found between energy drink intake per week and depressive mood. Moreover, the most frequent energy drink intake (three times or more per week) group showed the highest association with depressive mood (odds ratios (ORs); boys: ORs = 1.40, 95% confidence interval (CI): 1.25–1.56; girls: ORs = 1.61, 95% CI: 1.44–1.79) and suicide ideation (boys: ORs = 1.46, 95% CI: 1.27–1.69; girls: ORs = 1.36, 95% CI: 1.20–1.55). Conclusion: We observed that consumption of excessive amounts of energy drinks is associated with depression and suicide ideation. Therefore, appropriate regulation or education is needed to prevent adolescents from experiencing adverse outcomes.

With the increased life expectancy, people aging with spinal cord injury (SCI) are more likely to experience chronic conditions, including diabetes mellitus (DM). The results of previous literature related to the prevalence of DM are mixed and risk factors associated with diagnosis of DM after SCI are not well defined. This study aims to investigate the prevalence of DM and explore associated risk factors for diagnosis of DM among adults aging with long-standing spinal cord injury in the United States. This is a secondary data analysis using the National Spinal Cord Injury Model Systems Database. Participants included 516 people age 45 and older who have been living with SCI for more than 10 years. The prevalence of DM in this sample was 13.2%. Multivariate logistic regression, controlling for confounding variables, was conducted to identify risk factors associated with DM diagnosis in this sample. The multivariate logistic regression model found that the participants who responded with less severe SCI measured by the ASIA impairment scale were less likely to be diagnosed with DM (OR=0.332, p=.017). Also, DM was found to be significantly associated with BMI (OR=1.043, p=.010) and age (OR=1.038, p= .010) respectively. Duration of disability was not significantly associated with DM. Future research is needed to validate these findings and identify other common risk factors for DM such as diet/nutrition. Further, exploration of the effect size of risk factors is also warranted. Such findings will inform interventions to aid prevention and early detection of DM.

In this study, a pyramidal metal–dielectric hybrid-structure geometry with high broadband light absorption was prepared and applied as a photoelectrode for solar water oxidation. TiO2 was obliquely deposited on the pyramidal Au film, leading to asymmetrically thick pyramids. With the decoration of Au nanoparticles, the light absorption in the entire UV–visible region significantly increased to > 90%, which was examined by three-dimensional finite-difference time-domain simulations and confirmed by confocal spectral mapping techniques. By the introduction of Ti as the insertion layer, the alignment of bands at the TiO2/Au film interface was tuned, thereby promoting the separation of photogenerated carriers via the efficient transport of electrons to the Au film. This transport led to a remarkable enhancement in the photocurrent density (~0.16 mA/cm2) by 3.4 times compared to that observed for a flat TiO2 layer.

Localization and tracking of objects using data-driven methods is a popular topic due to the complexity in characterizing the physics of wireless channel propagation models. In these modeling approaches, data needs to be gathered to accurately train models, at the same time that user’s privacy is maintained. An appealing scheme to cooperatively achieve these goals is known as Federated Learning (FL). A challenge in FL schemes is the presence of non-independent and identically distributed (non-IID) data, caused by unevenly exploration of different areas. In this paper, we consider the use of recent FL schemes to train a set of personalized models that are then optimally fused through Bayesian rules, which makes it appropriate in the context of indoor localization.

Mueller polarimetric imaging is suitable for assessing the anisotropic and scattering properties of cervix. The extracellular matrix remodeling of cervical tissue in pregnant women is investigated using a Mueller Polarimetric Colposcope in vivo.

Mesenchymal-stem-cell (MSC)-based therapies have been recognized as promising strategies for the treatment of various injuries or diseases due to their unique characteristics, such as self-renewal, differentiation potential, and secretion of various bioactive molecules. However, MSC transplantation often results in low efficacy, including a cell viability loss and a low therapeutic activity. Alternatively, MSC spheroids have been studied to improve the viability and therapeutic activity of MSCs. Also, microencapsulation of cells can protect and retain the cells from harsh environments after transplantation. Here, MSC spheroids were formed in hyaluronic acid/alginate (HA@Alg) core-shell microcapsules and employed for neovascularization. A well-defined core-shell structure of HA@Alg microcapsules was produced by optimizing various electrospraying conditions. MSC spheroids could be spontaneously formed in the HA core of the microcapsules after 1 day of incubation. An enhanced secretion of various growth factors was found from MSC spheroids in HA@Alg. In vivo plug assay revealed the significant promotion of angiogenesis by MSC spheroids in HA@Alg compared to that by the controls (i.e., MSCs and MSC spheroids), which is likely due to the better retention of MSC spheroid forms in the microcapsules. Thus, the HA@Alg microcapsules embedding MSC spheroids will be greatly beneficial for various stem cell-based therapies.

The production of shape-controlled heterometallic nanoparticles (NPs) consisting of Pt and nonprecious metal oxides is crucial to demonstrate the composition–property relationship of NPs. Herein, we report a facile one-pot approach for the controlled synthesis of dumbbell-like Pt–Fe3O4–MnOx and dendritic Pt–MnOx NPs. The key to the success of this synthesis is in changing the quantity of Fe(CO)5 additive to control the reaction kinetics. In the absence of Fe(CO)5, dendritic Pt–MnOx NPs were synthesized through the assembly of small seed NPs. On the other hand, dumbbell-like Pt–Fe3O4–MnOx NPs were obtained in the presence of Fe(CO)5 through controlling the nucleation and growth of Fe and Mn on the Pt NPs, followed by air oxidation. Compared to a Pt/graphene oxide (GO) catalyst, dumbbell-like Pt–Fe3O4–MnOx NPs on GO showed an enhancement of specific activity toward the oxygen reduction reaction owing to the compressive-strain effect exerted on the Pt lattice.

We report a one-pot synthesis of hierarchical MnO/Pd-Fe3O4 and CoO/Pd-Fe3O4 nanocomposites containing scrolled multilayered nanosheets by controlled thermal decomposition of Fe(CO)5 and reduction of metal precursors [Pd(OAc)2]. During the synthetic process, particles of amorphous MnO and CoO are immobilized on the Pd-Fe3O4 support. These hierarchical nanocomposites follow a stepwise growth mechanism, initially forming Pd-Fe3O4 seeds aggregated from nuclei, followed by growth to produce multilayered MnO/Pd-Fe3O4 or CoO/Pd-Fe3O4 structures. To the best of our knowledge, this is the first report on the hydroboration of styrene with bis(pinacolato)diboron using heterogeneous nanocatalysts. Among these catalysts, CoO/Pd-Fe3O4 nanocomposites showed excellent performance due to the presence of a dual Pd and CoO catalytic system.

Mueller polarimetric imaging appeared to be very promising to detect the modifications in the microstructure of the uterine cervix due to the development of a precancerous lesion, thus providing very useful information for diagnostics to which practitioner cannot to access with classic color imaging. The first multispectral Mueller Polarimetric Colposcope (MPC) for the in vivo analysis of the uterine cervix will be presented. It has been obtained by miniaturizing a Mueller polarimetric imaging system and “grafting” it on a conventional colposcope, which is a low magnification binocular system, currently used in medical practice to examine the uterine cervix for detection of precancerous lesions. The multispectral MPC enables to obtain reliable Mueller polarimetric images in less than 2 seconds with a spatial resolution of 100 µm simultaneously at 450, 550 and 650 nm. Currently, it is being tested in vivo in the University Hospital of Kremlin Bicetre in France. In order to evaluate the performance of the technique, polarimetric images need to be compared with histological analyses of biopsies. The procedure developed in collaboration with medical doctors to obtain an accurate correlation between polarimetric images and biopsies will be described.

Mesenchymal stem cell (MSC) transplantation is promising for repairing heart tissues post myocardial infarction (MI). In particular, paracrine effects of the transplanted MSCs have been highlighted to play major roles in heart regeneration by secreting multiple growth factors and immune-modulatory cytokines. Nevertheless, its therapeutic efficacy still remains low, which is strongly associated with low viability and activity of the transplanted stem cells, because the transplanted MSCs are exposed to high shear stress during injection and harsh environments (e.g., high oxidative stress and host immune reactions) post injection. In this study, we aimed to develop novel injectable MSC-delivery microgel systems possessing high anti-oxidant activities. Specifically, we encapsulated MSCs in graphene oxide (GO)/alginate composite microgels by electrospraying. To further enhance the anti-oxidizing activities of the gels, we developed reduced MSC-embedded GO/alginate microgels (i.e., r(GO/alginate)), which have the potential to protect MSCs from the abovementioned harsh environments within MI tissues. Our in vitro studies demonstrated that the MSCs encapsulated in the r(GO/alginate) microgels showed increased viability under oxidative stress conditions with H2O2. Furthermore, cardiomyocytes (CMs), co-cultured with the encapsulated MSCs in transwells with H2O2 treatment, showed higher cell viability and cardiac maturation compared to monolayer cultured CMs, likely due to ROS scavenging by the gels and positive paracrine signals from the encapsulated MSCs. In vivo experiments with acute MI models demonstrated improved therapeutic efficacy of MSC delivery in r(GO/alginate) microgels, exhibiting significant decreases in the infarction area and the improvement of cardiac function. We believe that our novel MSC encapsulation system with GO, alginate, and mild reduction, which exhibits high cell protection capacity (e.g., anti-oxidant activity), will serve as an effective platform for the delivery of stem cells and other therapeutic cell types to treat various injuries and diseases, including MI.

People with long-standing physical disabilities are living longer than at any time in history, owing to advancements in medical science, rehabilitation, and social systems. Approximately 12–15 million people in the U.S. are aging with long-standing disabilities that were acquired before age 40 years. This population is forecast to grow, resulting in a subset within the aging community. More research is needed to increase understanding of successful aging with disabilities, the pathways of aging with disability, and unique characteristics of the aging process. The purpose was to define and clarify the conceptual meaning of aging with disability, identify its attributes, antecedents, and consequences, and explore the significance and implications of the concept in nursing. Rodgers’ evolutionary method of concept analysis was used. Three databases, CINAHL, PubMed, and PsycINFO were used to retrieve literature. Inclusion criteria were publication year from 2001 to 2019, peer-reviewed academic journals, and English-language. Exclusion criteria included other than physical disability such as developmental, learning, or intellectual disability, focus on the aging process of people without disability, the main topic on the perspectives of caregivers or health care providers. Thirty-five articles met inclusion criteria. The analysis identified three antecedents (e.g., contributing barriers), three attributes (e.g., premature aging), and three consequences (e.g., accommodation needs). An understanding of the antecedents, attributes, and consequences of aging with disabilities will enhance quality of care including effective prevention and communication. Findings will guide researchers in developing a framework or theory to increase understanding of aging in individuals who acquired disability early in life.

A facile synthetic strategy for a hybrid Cu2O/Pd–Fe3O4 nanocomposite via controlled thermal decomposition of Fe(CO)5 and reduction of Pd(OAc)2 and Cu(acac)2 was developed. The Pd precursor and amount of reducing agent used during the synthetic process controlled the morphology of the Cu2O/Pd–Fe3O4 nanocomposites. The prepared Cu2O/Pd–Fe3O4 nanocomposites showed excellent catalytic performance for C–H arylation, which can be attributed to the synergetic catalytic system formed from the catalytically effective Pd and Cu2O. Moreover, to the best of our knowledge, the C–H arylation of 4-nitroimidazoles with aryl iodides catalyzed by heterogeneous nanocatalysts has not been reported in the literature.

Stem cell transplantation has been recognized as a promising strategy to induce the regeneration of injured and diseased tissues and sustain therapeutic molecules for prolonged periods in vivo. However, stem cell-based therapy is often ineffective due to low survival, poor engraftment, and a lack of site-specificity. Hydrogels can offer several advantages as cell delivery vehicles, including cell stabilization and the provision of tissue-like environments with specific cellular signals; however, the administration of bulk hydrogels is still not appropriate to obtain safe and effective outcomes. Hence, stem cell encapsulation in uniform micro-sized hydrogels and their transplantation in vivo have recently garnered great attention for minimally invasive administration and the enhancement of therapeutic activities of the transplanted stem cells. Several important methods for stem cell microencapsulation are described in this review. In addition, various natural and synthetic polymers, which have been employed for the microencapsulation of stem cells, are reviewed in this article.

This paper presents a novel method of optimizing particle-suspended microfluidic channels using genetic algorithms (GAs). The GAs can be used to generate an optimal microchannel design by varying its geometrical parameters. A heuristic simulation can be useful for simulating the emergent behaviors of particles resulting from their interaction with a virtual microchannel environment. At the same time, fitness evaluation enables us to direct evolutions towards an optimized microchannel design. Specifically, this technique can be used to demonstrate its feasibility by optimizing one commercialized product for clinical applications such as the microchannel-type imaging flow cytometry of human erythrocytes. The resulting channel design can also be fabricated and then compared to its counterpart. This result implies that this approach can be potentially beneficial for developing a complex microchannel design in a controlled manner.

Asymmetric nozzle inlet was suggested for particles to converge into a highly confined region. The physical properties from the nano-scaled volumetric difference at nozzle inlet were investigated using computational fluid dynamics and particle motion measurement with fluorescence beads and erythrocytes. The asymmetric nozzle structure made particles converge efficiently without clogging at nozzle inlet. It could be used as a micro/nanofluidic unit for cell based assay in a microchip such as chip-based flow cytometer.

This paper presents a new sealing method for soft polymer (elastomer) microchips. A robust and reversible sealing method, which allows various materials to be bonded and sealed tightly with each other even in aqueous solutions, is developed. A poly (dimethylsiloxane) microchip system, which can actively generate bonding and sealing forces by itself, is invented. By inducing negative pressure into additional closed areas, an instant sucking disc is made. This disc is used to tighten up the conformal contact of soft polymers. Other functionalities of active sealing such as making reusable microchips, patterning cells and performing cellular assays in a single dish have also been examined and will be discussed hereunder. This technique gives a robust and universal solution for microchip sealing issues by sealing soft polymers with diverse materials under various conditions. Active sealing will simplify numerous assays in lab-on-a-chip industry and will open a new era for cellular microchip assays.

In this paper, we present a novel flow manipulation and signal detection scheme for a microfabricated fluorescence-activated cell sorter (μFACS). Optics setup was built on an inverted fluorescence microscope (IX71, Olympus, USA) and microchips were made of PDMS using soft lithography. Perfectly aligned axial illumination setup of the commercial microscope ensures effective signal detection. Hydrodynamic flow manipulation scheme is adopted for both flow focusing and cell sorting. Fast and robust sorting function is utilized by a nozzle flow from wide actuation channel. The sorting function is verified through real-time high-speed imaging. The captured images are used for adjusting delays between signal detection and sorting activation. The system automatically adjusts itself to any flow conditions, and so no adjustment is made to the flow parameters between runs. We believe that the proposed techniques will help breaking through the obstacles of μFACS system development.

The PDMS (poly(dimethyl siloxane)) replica molding is very useful for lab-on-a-chip development. This paper describes the several fabrication schemes of master fabrication for multi-height micro structures in PDMS microchip, and gives the overview over the technologies used for PDMS replica molding and channel closing with oxygen plasma treatment. Developed processes in the paper are good solution to fabricate the more complex structures in microfluidic lab-on-a-chip.

Stretching and folding, diffusion, and breakup are three basic processes that occur while mixing fluids. Although stretching and folding the interface of two fluids by rotation enables the mixing at microscale level in both low and high Reynolds number flows, rotation is not as effective at a low Reynolds number as at a high Reynolds number. Therefore, developing a rapid micromixer for microfluidic systems that can be used at a low Reynolds number is a challenging task, because it can demonstrate the full potential of microfluidic systems in commercial markets. Here, to enhance the mixing efficiency of a micromixer based on passive rotation, we present a breakup method. The breakup method not only generates interface actively but also enhances the diffusion process at the interface. With our novel design, over 70% mixing can be achieved only after passing through a 4 mm long microchannel. In this work, the mixer was easily fabricated with polydimethylsiloxane by soft lithography and a self-aligned bonding method with methanol. We analyzed the flow in the micromixer using the computational fluid dynamics method. Also, we conducted quantitative analyses using a confocal scanning microscope and image processing.

We have made detailed studies of pyrochlore compounds, R 2 Mo 2 O 7 with R = Nd , Sm , Gd , and Dy. For R=Nd and Sm, we found that apart from the ferromagnetic transition of Mo moments there is another transition of a reentrant spin glass type at lower temperatures, where both the magnetization and heat capacity data show anomalous features. We also observed that the AC susceptibility data are clearly frequency-dependent even in the ferromagnetic phase. In our pressure-dependent magnetization studies, the magnetization data of (Gd 1− x Dy x ) 2 Mo 2 O 7 for x=0, 0.1, 0.2 , and 0.4 are found to decrease continuously with pressures and, simultaneously, the ferromagnetic transition temperatures move towards lower temperatures. Eventually the ferromagnetic state of (Gd,Dy) 2 Mo 2 O 7 becomes unstable at higher pressures, and gives way to a spin glass phase that is found to exist at lower temperatures.

Endovascular microtools refers to catheter-like systems with microdevices that are put into arteries and veins. An intravascular micro active catheter system is the most advanced type of endovascular microtool. It consists of an active bending catheter and some functional catheters, such as intravascular micro ultrasound and micro drug infusion catheters. These systems are widely under development and commercialization. In this paper, we present a brief overview of the intravascular micro active catheter, followed by an explanation of the microsystems that have been developed at Seoul National University. This system consists of an active bending catheter, a micro drug infusion catheter and an ultrasound scanning catheter. All these systems show the proper functions for in vivo and in vitro tests.

Thirteen phenolic compounds from Aloe barbadensis (syn. A. vera) and A. arborescens were analysed by high performance liquid chromatography, using a reverse phase column eluted with a methanol: water gradient, and detected by UV at 293 nm. Aloesin, 8-C-glucosyl-7-O-methyl-(S)-aloesol, neoaloesin A, 8-O-methyl-7-hydroxyaloin A and B, 10-hydroxyaloin A, isoaloeresin D, aloin A and B, aloeresin E and aloe-emodin from A. barbadensis: and aloenin, aloenin B, 10-hydroxyaloin A, aloin A and B, and aloe-emodin from A. arborescens, were identified and quantified. The seasonal variation of two Aloe species was also examined by this method. © 1998 John Wiley & Sons, Ltd.

X-ray and neutron powder diffraction were employed to study the crystal and magnetic structures of pseudo-binary Laves-phase compounds (Zr 1− x Mn x )Co 2 and (Zr 1− x Mn x )Co 2.45 . It is found that the Zr 0.8 Mn 0.2 Co 2 compound has the MgCu 2 -type cubic structure (space group Fd3m), while Zr 0.64 Mn 0.36 Co 2.45 and Zr 0.64 Mn 0.36 Co 2 have the AuBe 5 -type (space group F-43m) cubic structure. All compounds are ferromagnets.

Wemeasuredtemperaturedependenceofvoltage–currentcharacteristicsofelectrochemicallypolymerizedpolypyrroleinmicronscaleusingscanningprobemicroscope.Themorphologyandthemagnitudeofroomtemperatureresistivity,q RT ¼ 0:016Xcm,aresimilartootherelectrochemicallysynthesizedpolypyrrole.I–Vcharacteristicsbecamenon-linearforT < 100Kandcanbefittedtofluctuation-inducedtunnelingconductionmodel. 2002ElsevierScienceB.V.Allrightsreserved. PACS:72.80.-r;72.80.Le;73.63.-b;73.63.NmKeywords:Polypyrrole;Micor-line;Electrochemicalsynthesis;Scanningprobemicroscope;Non-linearI-Vcharacteristics 1.IntroductionConjugatedpolymerhasinterestingphysicalproper-tiesincludingmetallicbehaviourandeventhesuper-conductivity [1] as well as applicability to electronicdevices such as LED [2] or field-effect transistor orconductivewireetc.Conductingpolymersuchaspoly-acetylene (PA), polypyrrole (PPy), polythiophen (PT)andpolyaniline(PANI)haslongbeeninvestigatedtoelucidate their intrinsictransport properties owing totheirlowdimensionality.Thelocalexcitationssuchassoliton [3], polaron and bipolaron are suggestedfor their conducting carriers. However the transportmechanisminconductingpolymerinnanoscaleisnotunderstoodwellyet.Recentlywehavereportedtrans-portmeasurementsofPAnanofibernetworkinmicronscale[4]andthatofPAsinglenanofiberin100nmscale[5].ContrarytothefibrillarstructureofPA,thegranularstructureofelectrochemicallypolymerizedconductingpolymermakesitdifficulttoapplythenanopatternedarrayofelectrodesfortheelectricalmeasurement.Inthecaseofusingtemplatesuchasanodicaluminumoxide(AAO) or zeolite, we can polymerize the conductingpolymer inside the template [6] and then separate itfromthetemplate.Othermethodstosynthesizealinearstructure of conducting polymer is using SPM localoxidation[7],e-beamirradiationtoPANI[8]orpoly-octylthiophene [9], self-assembled monolayer (SAM)pattern [10] and Langmuir–Bloddgett (LB) technique[11].STMlocaloxidationhassomedifficultiestomakealinearstructureinnarrowscaleduetotherandomnessofthegrowthdirection.UsingaSAMhaslimitationonthestamptogeneratetheSAMpatternanditisali-thography dependent technique. Here we present thetransport measurements of PPy line that is electro-chemicallypolymerizedbybiasingtothemetalcoatedSPMtipontopofthepatternedelectrodes.2.ExperimentalMicron and submicron electrodes for transportmeasurement were patterned using JEOL JBX5D-IIe-beamlithographysystem.300nmSiO

Endovascular is an English word meaning “within the vessel” from Latin endo (within) and vascularis (vessel) and is synonymous with intravascular. Cardiovascular refers to the interaction between the heart and the system of blood vessels from Greek cardio (heart) and Latin vascularis (vessel). In this chapter the word endovascular is used to refer to the vascular system and endovascular microtool refers to a utensil that transports substances to tissues. An endovascular microtool is designed for use in surgical operations on vascular systems that remove byproducts of metabolism, maintain the body temperature, and control the oxygen and nutrient supply. Blood flows rapidly in the vascular system. The average human male has 5 to 6 liters of blood, and blood circulates through the body in 30 seconds [78].

This paper presents a novel method for an on-chip erythrocyte deformability test under optical pressure, especially to enhance the level of sensitivity with respect to the detection of cancerous diseases. To demonstrate the performance and sensitivity of the combined method, we introduce the concept of transit velocity, a modified elongation index, and shape recovery time of individual erythrocytes in a strictly confined region (2 microm deep, 4 microm wide, and 100 microm long). Finally, we investigate a synergy or convergence effect due to the combination of these parameters for in situ detection of cancerous diseases under optical pressure.

Although CD4+ T-cells are an important target of HIV detection, there have been still major problems in making a diagnosis and monitoring in the third world and the region with few medical facilities. Then, it is necessary to use portable diagnosis devices at low cost when you put an enumeration of CD4+ T-cells. In general, the counting of CD4 below 200cells/uL makes it necessary to initiate antiretroviral treatment in adults (over 13 years old). However, lymphocyte subsets (including CD4 counts) of infants and young children are higher than those of adults. This fact shows the percentage of CD4+ T-cells of blood subsets, i.e., CD4/CD45%, CD4/CD8% or CD4/CD3% means a more reliable indicator of HIV infection than absolute counts in children. To know the percentage of CD4+ T-cell by using two fluorescent dyes of different emission wavelength, at least, one laser and two PMT detectors are in general needed. Then, it is so hard to develop a portable device like a 'toaster size' because this makes such a device more complex including many peripheral modules. In this study, we developed a novel technique to control the intensity of fluorescent dye-doped silica nanoparticles. I synthesized FITC-doped silica nanoparticles conjugated CD4 antibody 10 times brighter than FITC-conjugated CD45 antibody. With the difference of intensity of two fluorescent dyes, we measured two parameters by using only a single detector and laser. Most experiments were achieved with uFACS (microfabricated fluorescence-activated cell sorter) on an inverted microscope (IX71, Olympus). In conclusion, this method enables us to discriminate the difference between CD4 and CD45 in an intensity domain simultaneously. Furthermore, this technique would make it possible develop much cheaper and smaller devices which can count the number of CD4 T-cells.

This paper presents a novel way of designing a flow focusing channel for microchip flow cytometers. With this method we increased throughput and sensitivity of particle detection at the same time. Generally, to increase the detection throughput of a flow cytometer, the speed of the flow inside the focusing channel needs to be increased, hence reducing the time of exposure to laser beam. With the shorter exposure time, both the fluorescence and scatter signal from the target particles become dimmer. To increase the sensitivity of signal detection, however, the speed of the flow should be decreased so as to decrease throughput of detection. To overcome this dilemmatic problem, we integrated an expansion channel inside a focusing channel. Signals from particles in an expansion channel were about 10 times brighter than those in a normal channel. With this enhanced sensitivity, we could also speed up the inlet flow, which in turn increases the overall throughput of detection.

A combined microchannel-type erythrocyte deformability test with optical tweezers has been developed especially for more sensitive detection of cancerous diseases. To demonstrate the performance and sensitivity of the microchannel-type method, we measured the transit velocity of individual erythrocytes passing through a specific confinement region and calculated the modified elongation index defined by the ratio of the width of the microchannel to the elongated length of the squeezed erythrocytes. To know exactly the effect of optical tweezers on erythrocytes, we investigated several morphologies of optically deformed erythrocytes and measured the shape recovery time of erythrocytes in a static aqueous solution under various powers (~ 24 mW) of 1064-nm laser by a dual-trap optical tweezers. Finally we combined these two methods by considering the key parameters of erythrocyte deformability. The results show that the ambiguity of the overlapped experimental data from microchannel-type erythrocyte deformability test was conspicuously reduced, and that the subtle change (s 100–200 ms) in shape recovery time which is one of mechanical properties of erythrocyte membrane surface was remarkably amplified to readily discriminate the difference (s 2–3 s) between normal and cancerous blood. This suggests the combined method is more sensitive enough to pinpoint the minor quantitative differences between individual erythrocytes, especially in the field of cancer and cardiovascular diseases.

In this study, single red blood cell (RBC) deformability test is performed by using optical trapping in poly(dimethylsiloxane) PDMS microfluidic chip. The salient feature of this method is to provide more extensional recovery time of individual RBCs in order to tell the minor difference of RBC deformability between normal and abnormal blood.

Plasma separation from whole blood using microfluidics was investigated. We suggested modified channel geometry called "corner-edge" to enhance plasma skimming effect at branching channel. To evaluate separation efficiency, microfluidic chip was fabricated with silicone elastomer and glass. The efficiency of separation was above 99% comparing with whole blood hematocrit. This microfluidic unit could be integrated with microchannel network for lab-on-a-chip applications such as immunoassay.

The relation between erythrocyte deformability and cancer has been proved in medical fields, but it is very difficult to systemize and commercialize the traditional schemes for erythrocyte deformability assessment. In this work, a desk-top type RBC Hemocytometer system with PDMS microchip has been developed for the assessment. Macrochannels with microfiltering structure in the microchip make the erythrocyte deformed, and with an UV optical array system and C language based image processing software, filter-pass-shape and filter-pass-velocity of erythrocytes are sequentially analyzed. In the comparative studies with blood from cancerous patients and control blood, we could obtain statistically acceptable data that can distinguish cancerous from control regardless of the cancer infected regions. To enhance the performance of the system, comparative studies changing the materials of the chip (silicon-glass, PDMS and PMMA) and sectional surface characteristics control have been accomplished with notable results. This RBC Hemocytometer system can be applied as a practical diagnostic apparatus in early detection of cancer.

Endovascular micro tools mean the catheter-like systems with micro devices which are put into arteries and veins. An intravascular micro active catheter system is the most famous type of endovascular micro tools and it consists of active bending catheter and some functional catheters such as guide wire, balloon catheter, angioscope, drug delivery catheters, micro surgery tools and so on. These systems have been widely developed and commercialized. A brief overview of the intravascular micro active catheter is presented, followed by an explanation of the micro systems being developed at the Seoul National University. This system consists of an active bending catheter, micro drug infusion catheter and ultrasound-scanning catheter. All of these systems show the proper functions in in-vivo and in-vitro tests.

The authors have developed an intravascular micro active catheter system for microsurgery in human vascular systems, such as cerebrovascular and coronary arteries. Also this system can be applied to laparoscopical treatment. It consists of the micro active bending catheter and some functional catheters. The former is a tube-like catheter which has an outer-diameter of 3.0 mm, an inner-diameter of 2.0 mm and a length of 1000 mm. It's inner hole is a pathway for the functional catheters, such as conventional guide wire, balloon catheter, conventional suction tube, micro ultrasound probe catheter, fiber optics (angioscope), angioplatic devices and drug injection lines. This active bending catheter is actuated with three SMA (shape-memory-alloy) zigzag type springs-SMA wires are connected with plastic and brass connection links. This actuator can be bent to any direction with the PWM controlled electric current. The authors also developed a micro drug infusion catheter and a micro ultrasound probe catheter fitted to the inner hole of active bending catheter. All of these systems were evaluated with the human mock circulation system. They can be introduced through 90/spl deg/, 120/spl deg/, 180/spl deg/ crooked branches to the brachiocephalic artery, common carotid artery, subelavian artery and so on in the mock circulation system. Also, the authors tested this endoscope system in vivo by performing laparoscopical surgery on a pig. They could easily induce the catheter to the point they wanted in the pig ovary.

There are a lot of clinical studies about the relations between the erythrocyte deformability and the local blood flow mediated diseases like cancer. [1,2] Normally they have used the hemorheological techniques for the erythrocyte deformability assessment, but these have the practical limitations.[3] This paper presents the advanced schemes of the blood cell deformability measurement using PDMS micro fluidic chips. Developed microchip and system can characterize the mechanical properties of cancerous erythrocyte, and can be used a practical pre-diagnostic apparatus for the early detection of cancer.

Dilution of microfluids is very complex because of the flexibility of microfluids concerned with the channel size, surface characteristics and Reynolds number. With the simulation results of dilution in microchannel, we developed the novel serial dilution chips made of PDMS and glass plate. These chips can be applied to the cell toxicity test, bacteria counting test and Minimal Inhibitory Concentration test of antibiotics and so on.

In this article, we report a novel combined microchannel-type erythrocyte deformability test with optical tweezers which can enhance the level of sensitivity with respect to the detection of cancerous diseases. To demonstrate the feasibility of the combined method, we introduce three major parameters, the transit velocity, a modified elongation index, and the shape recovery time of a single erythrocyte in a specifically confined region under dierent powers of an infrared laser. These parameters are geometrically determined and experimentally evaluated for a special blood-related disease, leukemia. The results support this method has a good detection sensitivity enough to pinpoint a minor dierence in the deformability between individual erythrocytes. Furthermore, such a complementary combination of optical tweezers with microfluidic structures will be helpful for comprehensively understanding what significant eect the mechanical properties of erythrocytes have on the multiple chemical reactions inside a living erythrocyte.