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Direct air capture (DAC) of CO 2 using solid sorbents is a promising negative emission technology to reduce global greenhouse gas emissions. Despite many advantages of alkyl-amine-based adsorbents, degradation caused by urea formation under a dry CO 2 regeneration remains a challenge. Herein, we hypothesized that certain nitrogen-containing heterocyclic compounds can contribute toward suppressing urea formation by the ring structure and thus, selected piperazine (PZ) as a representative chemical. PZ was wet-impregnated onto a silica aerogel (PZ/silica) with controlled pore size and volume. The synthesized sorbents exhibited high CO 2 sorption uptake and kinetics. In a cyclic test via temperature swing adsorption (adsorption: calibrated 200 ppm CO 2 ; desorption: dry CO 2), PZ/silica exhibited stable and high adsorption capacities (average 1.3 mmol/g over 24 cycles). The suppression of urea formation in PZ/silica under extended dry CO 2 regeneration was demonstrated using an in-situ diffuse reflectance infrared Fourier transform spectroscopy, thereby proving the above hypothesis. PZ/silica showed good anti-oxidation performance of CO 2 capture, 1.6 mmol CO 2 /g, after 12 h oxidation under 21% O 2 balanced with N 2. Besides, PZ/silica maintained a CO 2 adsorption uptake of 0.79 mmol/g after the preliminary adsorption of H 2 O. This study proposes a novel way to synthesize DAC solid adsorbents using N-containing heterocyclic compounds. [Display omitted] • Piperazine was wet-impregnated onto silica aerogel (PZ/silica) as CO 2 sorbents. • PZ/silica showed CO 2 uptake of 1.3 mmol/g at 25 °C (200 ppm CO 2) and fast kinetics. • PZ/silica was stable under 24-cycle hot dry CO 2 desorption due to inhibition of urea. • CO 2 uptake of PZ/silica was improved (1.6 mmol/g) after 12 h oxidation test. • Sorbent sorbed CO 2 (0.79 mmol/g) after pre-sorbed H 2 O, being suitable for humid DAC. [ABSTRACT FROM AUTHOR]

A portable sweat rate sensor integrated with a thermo-pneumatic actuator for automatic ventilation has been proposed and experimentally verified its performance. The previous forced ventilation sweat rate sensors using external ventilating devices had the problem of the bulky size with the lack of portability. The previous natural ventilation sweat rate sensors with portable sizes meanwhile required a manual ventilation per each measurement. The total weight of the present portable sweat rate sensor is 6.2% of that of the previous forced ventilation sweat rate sensors. The integrated thermo-pneumatic actuator lifts the humidity measuring chamber above the skin for automatic natural ventilation. The portable sweat rate sensor, having a size of 38 ± 0.5 mm × 41 ± 0.5 mm × 29 ± 0.5 mm with a total weight of 63 ± 1 g, is capable of lifting the humidity chamber 1.91 ± 0.27 mm above the skin in a movement cycle period of 3 min. The portable sweat rate sensor measures the sweat rate with a sensitivity of 0.056 (pF/s)/(g/m 2 h) and a linearity of 99.1% in a sweat rate range of 3.76–137.68 g/m 2 h. The portable sweat rate sensor is insensitive to the environmental air flow, and thus demonstrates high potential for mobile human thermoregulatory status monitoring applications, such as human monitoring jackets and cognitive air-conditioning systems based on human sweat. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present a micro-DMFC (Direct Methanol Fuel Cell), whose uniform contacts at electrode–electrolyte interface is achieved by supporting structures on the back-side of the microcolumn electrodes (multi-window electrode), and an integrated serial stack structure using pair-electrodes and skew-symmetrical configuration for minimal voltage drop in cell interconnections. We fabricate a set of single DMFC with three different types of the multi-window electrodes, having an identical projected electrode area of 10mm×10mm: the 4-window microcolumn electrode (ME4), the 16-window microcolumn electrode (ME16) and the 16-window planar electrode (PE16). The 2- and 4-cell stacks have been fabricated in the integrated stack structure, where the common polymer electrolyte is sandwiched by the ME16 electrode pairs. In the experimental study, the single cells with ME16 and PE16 electrodes show the maximum power densities of 31.04±0.29μW/cm2 and 9.75±0.29μW/cm2, respectively; thus indicating the microcolumn electrode (ME16) generates the power density 3.2 times higher than the planar electrode (PE16) does. The single cell tests of ME16 and ME4 electrodes show the maximum power of 31.04±0.29μW/cm2, and 25.23±2.7μW/cm2, respectively; thus demonstrating the increased multi-window frame reduces the normalized standard power deviation (standard deviation over the average power). The normalized deviation of 0.11 in ME4 cell has been reduced to 0.01 in ME16 cell due to the increased window frames. The 2-cell and 4-cell stacks show the maximum power density of 92.6±0.31μW/cm2, and 329.8±0.47μW/cm2, respectively. The maximum power density of 4-cell stack is 15.7 times higher than that of the single cell, indicating that the present integrated serial stack structure is effective for accumulating cell power. [Copyright &y& Elsevier]

Abstract: This paper presents a three-dimensional (3D) tumor spheroid chip where the pharmacokinetic (PK) drug elimination model is developed by balanced droplet dispensing. The PK model should reflect the exponential decrease of drug concentration in a body to improve the reliability of cell-based screening assay. The previous cell chips, however, maintain the concentration of anti-cancer agents at constant or discretely decrease the concentration level by manual process. In the present chip where medium droplet dispensers are integrated on a well array, the small droplets of fresh medium and well waste are autonomously replaced each other, the exponential elimination of drug concentration in the well is provided. In the experimental study, we demonstrated that the present chip successfully develops the exponential elimination model using fluorescein isothiocyanate (FITC) and cisplatin. Although the exponential decay of cisplatin in the present chip did not show significant effect biologically due to the current protocol where 3 days of constant concentration pre-treatment is performed, we observed different growth pattern of H358 spheroids depending on peak concentration of 0, 1, 10, and 100μM. The present chip has potential for analyzing the response of 3D tumor spheroids in the pharmacokinetically relevant drug elimination model for high-reliability spheroid-based drug screening chip. [Copyright &y& Elsevier]

Abstract: Frequency tunable comb resonators have been successfully designed and demonstrated based on a closed-form approach of a curved comb finger contour. Experimentally, the resonant frequency of a laterally driven comb resonator with 186 pairs of curved finger contour has been reduced by 55% from the initial frequency of 19kHz under a bias voltage of 150V. The corresponding effective stiffness has been decreased by 80% from the initial value of 2.64N/m. This closed-form design approach could be extended to microsystems based on electrostatic comb-shape structures such as microaccelerometers, microgyroscopes, and micromechanical filters. [Copyright &y& Elsevier]

A femoral shaft fracture is usually a high-energy injury and, thus, is likely to be accompanied by an injury of adjacent joints such as a knee ligament injury. However, these associated injuries are often neglected because of severe pain and deformity. The purpose of the current study is to evaluate the incidence, type and risk factors of ipsilateral knee injuries associated with femoral shaft fractures. A total of 429 femoral shaft fractures were included in this study from January 2010 to September 2015. There were 320 males and 109 females, with mean age of 40.7 years (range, 15-88). Exclusion criteria were skeletally immature patients and patients with metabolic bone disease such as osteoporosis, atypical femoral fractures, and pathologic fractures. The incidence and type of knee injury were identified, and the injury mechanisms, AO/OTA classification of the femoral shaft fractures, were analysed for assessment of risk factors for knee injuries combined with femoral shaft fractures. Knee injuries were found in 131 cases. Knee ligament injuries were identified in 87 cases. There were 20 posterior cruciate ligament injuries, 11 anterior cruciate ligament (ACL) injuries, 16 medial collateral ligament (MCL) injuries, 8 lateral collateral ligament (LCL) injuries, and 32 multi-ligament injuries. In 24 cases, ligament injuries were not detected before internal fixation of femoral shaft fractures. Average time of diagnosis for ligament injury after fixation in these neglected cases was about 10.6 weeks (range, 1-32). Fractures around the knee joint were identified in 69 cases; there were 32 patellar fractures, 14 distal femoral intra-articular fractures, 14 tibia plateau fractures, 3 proximal fibular fractures, and 6 combined fractures. Male sex, type C fracture of AO/OTA classification, and motor vehicle accidents were identified as risk factors for associated ipsilateral knee injuries in femoral shaft fractures. Knee injuries were identified in approximately 30% of femoral shaft fractures. About 30% of ligament injuries were not detected before internal fixation of femoral shaft fractures. Care should be taken since knee injuries can be accompanied by ipsilateral femoral shaft fractures. [ABSTRACT FROM AUTHOR]

The metastasis of cancer is strongly associated with the spread of circulating tumor cells (CTCs). Based on the microfluidic devices, which offer rapid recovery of CTCs, a number of studies have demonstrated the potential of CTCs as a diagnostic tool. However, not only the insufficient specificity and sensitivity derived from the rarity and heterogeneity of CTCs, but also the high-cost fabrication processes limit the use of CTC-based medical devices in commercial. Here, we present a low-cost fabric sheet layers for CTC isolation, which are composed of polyester monofilament yarns. Fabric sheet layers are easily functionalized with graphene oxide (GO), which is beneficial for improving both sensitivity and specificity. The GO modification to the low-cost fabrics enhances the binding of anti-EpCAM antibodies, resulting in 10–25% increase of capture efficiency compared to the surface without GO (anti-EpCAM antibodies directly onto the fabric sheets), while achieving high purity by isolating only 50–300 leukocytes in 1 mL of human blood. We investigated CTCs in ten human blood samples and successfully isolated 4–42 CTCs/mL from cancer patients, while none of cancerous cells were found among healthy donors. This remarkable results show the feasibility of GO-functionalized fabric sheet layers to be used in various CTC-based clinical applications, with high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

Previously, a high-molecular weight sericin was developed using gamma irradiation to change its molecular structure. Although the physiological activity of sericin was enhanced by gamma irradiation, its molecular weight was too high, having increased by about 400 kDa. In this study, we tried to improve the commercial applicability of sericin by optimizing the gamma irradiation dose. A sericin solution (100 mg/ml) was prepared with a pH of 5.0, 6.0, 7.0, 8.0, and 9.0, and gamma-irradiated at the absorbed doses of 2.5, 5.0, 7.5, and 10 kGy. Non-irradiated solution was used as a control. The samples were analyzed for their solubility and DPPH radical scavenging activity. In the solubility analysis, significant differences in molecular weight were not seen according to irradiation dose, whereas their solubility and antioxidant activity were changed. Sericin irradiated with 5 kGy gamma rays at 10 mg/ml exhibited macrophage polarization to the M2 phenotype in cells; this outcome was associated with a reduction of NF-κB activation as a defense against inflammatory reactions. These findings suggest that gamma irradiation of less than 10 kGy is an effective method for the practical use of sericin. This study has important implications for the use of highly functional biotechnology products, as anti-inflammatory activity was increased without changing molecular weight. • The optimal sericin concentration and optimal absorbed dose condition were established. • Exposure of sericin to gamma irradiation was accompanied by an increase in its solubility. • Gamma-irradiated sericin negatively regulates LPS-stimulated inflammation through NF-κB deactivation. • The anti-inflammatory effect of gamma-irradiated sericin may be mediated by M2 macrophage polarization. [ABSTRACT FROM AUTHOR]