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High loading of aligned graphene filler is effective for fabricating polymer nanocomposites with drastically improved properties, while practical preparation of such composites remains elusive. This paper reports on a method of preparing polyimide (PI, BPDA/PDA) nanocomposites containing highly loaded graphene fillers that are uniformly aligned parallel to the coating substrate in the PI matrix. The highly aligned graphene/PI film was achieved by infiltrating water-soluble poly(amic acid) ammonium salt (PAAS) into the scaffold of the graphene oxide liquid crystal. After thermal treatment, a freestanding reduced graphene oxide/polyimide (rGO/PI) film was prepared with the imidization of PAAS and reduction of graphene oxide. Owing to the excellent mechanical properties of the infiltrated PI, the hardness and modulus of the rGO/PI film were as high as 0.9 GPa and 9.3 GPa, respectively. In addition, the rGO/PI film was highly conductive, with an electrical conductivity of 446 S/m, because of the well-connected electrical pathways of the highly loaded and aligned graphene sheets.

Free-floating micro-mobility as a mobility solution is becoming increasingly popular in cities. In this study, the travel patterns of free-floating electric bike-sharing service (FFEBSS) users before and during the COVID-19 pandemic were explored using big data and data mining. Existing real-time data studies provide a limited understanding of trip patterns and the characteristics of each user. Interpretations concerning the occurrence of life-changing events such as the COVID-19 pandemic are important. This study aimed to understand each user over 13 months comprising multiple time frames of market trends, seasonal change, and the COVID-19 pandemic outbreak. Multiple features were extracted from each user to explain the hidden data characteristics, and a data mining method was employed for clustering and evaluating user similarities with the extracted features. The results showed that FFEBSS users demonstrated a moderately stable travel pattern despite the COVID-19 pandemic, indicating the possibility of micro-mobilities being well adoptedas our future urban transportation.

Herein, a functionalized nanoporous graphene (FNG) membrane was developed to mitigate the contemporary issues affecting graphene oxide (GO) membranes, such as the low flux induced by its long tortuosity and poor membrane stability in aqueous solvents. GO was thermally activated at 650 °C to prepare a nanoporous carbon sheet with a turbostratic structure (pore size

Graphene oxide (GO) has been widely used for the fabrication of nanofiltration membranes because precise molecular sieving can be achieved through the narrow interlayer spacing between stacked GO sheets. Herein, the scalable and continuous fabrication of a GO membrane is demonstrated by using a slot-die coater at a coating speed of 6 mm s−1. The thickness of the GO membrane can be controlled in 100-nm scale depending on the concentration of the GO solution and substrate morphology. Moreover, the coating layer and d-spacing (6.5–7.5 A) of the GO membrane is preserved, even in aqueous solution, as GO is partially reduced by NaOH treatment (so-called deoxygenated GO, dGO). A membrane performance test reveals that the dGO membrane is effective for filtering sub-nanometer-size dye molecules with a rejection rate of up to 99% (brilliant blue G) and a pure water permeance of 30 LMH bar−1. The dGO membrane operates stably under cross-flow and high pressure up to 12 bar. Scale-up of the GO membrane fabrication using the slot-die coating technique is feasible because the coating process is continuous.

Nucleic acid amplification techniques are used frequently for rapid diagnosis of viral diseases. In this study, a real-time polymerase chain reaction protocol that uses primers specific for the viral VP4 gene and the commercial SYBR Green reagent were evaluated for the quantitative measurement of human rotavirus (HRV) RNA in human stool specimens. SYBR Green I detection involved analysis of the melting temperature of the PCR product and measurement of fluorescence at the optimum temperature. The assay resulted in a sensitive and reproducible detection of targets ranging from low (10(2)rotavirus cDNA copies/reaction) to high numbers (10(6)rotavirus cDNA copies/reaction). No cross-reaction was found with crude cell culture stocks of coxsackievirus, echovirus, poliovirus, hepatitis A virus and adenovirus. Analysis with the HRV cDNA standard demonstrated high reproducibility with a coefficient of variation (CV) of 0.2-0.9%. Daily performance among three different laboratories showed a CV no greater than 8%, indicating an intermediate level of variation. These results demonstrate the feasibility of this method for quantitative analysis of human rotavirus in clinical samples.

Protection of pancreatic islet beta cells from pro-inflammatory cytokines-induced cell death and functional impairment is a key issue in developing therapeutic interventions of type 1 diabetes mellitus including islet transplantation. The effects of IL-6 on the protection of beta cells in vitro and in vivo were examined. Freshly isolated islets or MIN6 beta cells, when pre-incubated with IL-6, showed significantly higher viabilities measured by MTT assay and FACS analysis of PI stained cells against pro-apoptotic signaling delivered by IL-1beta, TNF-alpha and IFN-gamma. Insulin secretory function was also significantly protected in static culture with glucose and KCl stimulation. In vivo assessment using marginal mass syngeneic islet transplantation in mouse model revealed IL-6 conferred significantly better blood glucose control and graft survival rate over 50 days. Conclusively, IL-6 protects pancreatic islets or beta-cells from inflammatory cytokines-induced cell death and functional impairment both in vitro and in vivo. This strategy could be exploited in the clinical setting to maintain functional islet mass.