Mobile microrobots, which can navigate, sense, and interact with their environment, could potentially revolutionize biomedicine and environmental remediation. Many self-organizing microrobotic ...collectives have been developed to overcome inherent limits in actuation, sensing, and manipulation of individual microrobots; however, reconfigurable collectives with robust transitions between behaviors are rare. Such systems that perform multiple functions are advantageous to operate in complex environments. Here, we present a versatile microrobotic collective system capable of on-demand reconfiguration to adapt to and utilize their environments to perform various functions at the air-water interface. Our system exhibits diverse modes ranging from isotropic to anisotrpic behaviors and transitions between a globally driven and a novel self-propelling behavior. We show the transition between different modes in experiments and simulations, and demonstrate various functions, using the reconfigurability of our system to navigate, explore, and interact with the environment. Such versatile microrobot collectives with globally driven and self-propelled behaviors have great potential in future medical and environmental applications.
Pt/CeO2 catalysts with various Pt loadings were prepared by a conventional incipient wetness impregnation method that employed CeO2 cubes (c‐CeO2), rods (r‐CeO2), and octahedra (o‐CeO2) as the ...support and Pt(NH3)4(NO3)2 as the metal precursor. Their structures and catalytic activities in CO oxidation in excess O2 and the preferential oxidation of CO in a H2‐rich gas (CO‐PROX) were studied, and strong morphology effects were observed. The impregnated Pt precursor interacts more strongly with CeO2 rods and cubes than with CeO2 octahedra, and the reduction/decomposition of the Pt precursor impregnated on CeO2 octahedra is easier than that on CeO2 rods and cubes. With the same Pt loading, the Pt/o‐CeO2 catalyst contains the largest fraction of metallic Pt, whereas the Pt/c‐CeO2 catalyst contains the largest fraction of Pt2+ species. The reducibility of pure CeO2 and CeO2 in the Pt/CeO2 catalysts follows the order r‐CeO2>c‐CeO2>o‐CeO2, and the reducibility of CeO2 depends on the Pt loading for the Pt/c‐CeO2 catalysts but not much for the Pt/r‐CeO2 and Pt/o‐CeO2 catalysts. The catalytic performance of Pt/CeO2 catalysts in both CO oxidation and the CO‐PROX reaction follows the order Pt/r‐CeO2>Pt/c‐CeO2> Pt/o‐CeO2. The Pt0‐CeO2 ensemble is more active than the Pt2+‐CeO2 ensemble in the catalysis of CO oxidation in excess O2. H2‐assisted CO oxidation catalyzed by the Pt/CeO2 catalysts was observed in the CO‐PROX reaction, and the Pt2+ species and CeO2 with a large concentration of oxygen vacancies constitute the active structure of the Pt/CeO2 catalyst for the CO‐PROX reaction. The effect of the morphology of the CeO2 support in the preparation, metal–support interaction, and catalytic performance of Pt/CeO2 catalysts can be correlated the exposed crystal planes and surface composition/structure of the CeO2 support with different morphologies. These results not only demonstrate that the structure and catalytic performance of oxide‐supported catalysts can be tuned by controlling the morphology of the oxide support but also deepens the fundamental understanding of CO oxidation reactions catalyzed by Pt/CeO2 catalysts.
Get Ce‐rious: Pt/CeO2 catalysts that employ CeO2 cubes, rods, and octahedra as the support exhibit a strong morphology effect on the Pt precursor–CeO2 interaction, Pt–CeO2 interaction, structure, and catalytic performance. The catalytic performance of various Pt/CeO2 catalysts in CO oxidation and the preferential oxidation of CO in a H2‐rich gas (PROX) follows the order Pt/CeO2‐rods> Pt/CeO2‐cubes> Pt/CeO2‐octahedra.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
To determine the priority hazard in drinking water, disability-adjusted life years (DALYs) method was used to evaluate the disease burden induced by trihalomethanes (THMs) and low-level arsenic ...through multiple exposure routes based on the two-year sampling from drinking water in Xi'an city, Northwest China. The average concentrations of chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), bromoform (TBM) and arsenic were 12.67 μg/L, 1.42 μg/L, 0.60 μg/L, 0.13 μg/L and 1.00 μg/L, respectively, and the total lifetime cancer risks for all THMs and arsenic were 8.54 × 10−6 and 4.02 × 10−5, which were 8.54 and 40.2 times of the negligible risk level (1.00 × 10−6), respectively. The DALYs estimation showed that the total DALYs lost for all age groups was 32.62 person-year, and the average individual DALYs lost was 4.77 × 10−6 per person-year (ppy), which was 4.77 times of the reference level (1.00 × 10−6 ppy). About 72.07% of the total disease burden was due to arsenic, which was considered to be the priority hazard in Xi'an drinking water. The age group of 75–80 years was found to be most vulnerable to the induced cancer risk, and skin cancer had the highest disease burden (2.24 × 10−6 ppy). Due to the relatively high incidence rates of lung cancer and skin cancer, most DALYs lost for males were 2–4 times to that for females in the same age group. Oral ingestion made the most contribution (88.58%) to the total disease burden, followed by inhalation of THMs (11.30%), whereas dermal absorption showed negligible risk (0.12%). As the first to compare the cancer risks of arsenic and THMs to the public in DALYs in China, this study might be useful for potential strategies of risk control and management of hazardous agents in drinking water.
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•The individual DALYs lost induced by THMs and low-level arsenic was 4.77 × 10−6 ppy.•Skin cancer had the highest disease burden of 2.24 × 10−6 ppy.•Most DALYs for males were 2–4 times to that for females in the same age group.•Oral ingestion made the most contribution (88.58%) to the total disease burden.•72.07% of the disease burden was due to arsenic, which was the priority hazard in Xi'an drinking water.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
By using increasingly popular smartphones, participatory sensing systems can collect comprehensive sensory data to retrieve context-aware information for different applications (or sensing tasks). ...However, new challenges arise when selecting the most appropriate participants when considering their different incentive requirements, associated sensing capabilities, and uncontrollable mobility, to best satisfy the quality-of-information (QoI) requirements of multiple concurrent tasks with different budget constraints. This paper proposes a multitask-oriented participant selection strategy called "DPS," which is used to tackle the aforementioned challenges, where three key design elements are proposed. First is the QoI satisfaction metric, where the required QoI metrics of the collected data are quantified in terms of data granularity and quantity. Second is the multitask-orientated QoI optimization problem for participant selection, where task budgets are treated as the constraint, and the goal is to select a minimum subset of participants to best provide the QoI satisfaction metrics for all tasks. The optimization problem is then converted to a nonlinear knapsack problem and is solved by our proposed dynamic participant selection (DPS) strategy. Third is how to compute the expected amount of collected data by all (candidate) participants, where a probability-based movement model is proposed to facilitate such computation. Real and extensive trace-based simulations show that, given the same budget, the proposed participant selection strategy can achieve far better QoI satisfactions for all tasks than selecting participants randomly or through the reversed-auction-based approaches.
Generally, if a user wants to use numerous different network services, he/she must register himself/herself to every service providing server. It is extremely hard for users to remember these ...different identities and passwords. In order to resolve this problem, various multi-server authentication protocols have been proposed. Recently, Sood et al. analyzed Hsiang and Shih's multi-server authentication protocol and proposed an improved dynamic identity based authentication protocol for multi-server architecture. They claimed that their protocol provides user's anonymity, mutual authentication, the session key agreement and can resist several kinds of attacks. However, through careful analysis, we find that Sood et al.'s protocol is still vulnerable to leak-of-verifier attack, stolen smart card attack and impersonation attack. Besides, since there is no way for the control server CS to know the real identity of the user, the authentication and session key agreement phase of Sood et al.'s protocol is incorrect. We propose an efficient and security dynamic identity based authentication protocol for multi-server architecture that removes the aforementioned weaknesses. The proposed protocol is extremely suitable for use in distributed multi-server architecture since it provides user's anonymity, mutual authentication, efficient, and security.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK
Long non-coding RNAs (lncRNAs) involved in metabolism are recognized as significant factors in breast cancer (BC) progression. We constructed a novel prognostic signature for BC using ...metabolism-related lncRNAs and investigated their underlying mechanisms. The training and validation cohorts were established from BC patients acquired from two public sources: The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). The prognostic signature of metabolism-related lncRNAs was constructed using the least absolute shrinkage and selection operator (LASSO) cox regression analysis. We developed and validated a new prognostic risk model for BC using the signature of metabolism-related lncRNAs (SIRLNT, SIAH2-AS1, MIR205HG, USP30-AS1, MIR200CHG, TFAP2A-AS1, AP005131.2, AL031316.1, C6orf99). The risk score obtained from this signature was proven to be an independent prognostic factor for BC patients, resulting in a poor overall survival (OS) for individuals in the high-risk group. The area under the curve (AUC) for OS at three and five years were 0.67 and 0.65 in the TCGA cohort, and 0.697 and 0.68 in the GEO validation cohort, respectively. The prognostic signature demonstrated a robust association with the immunological state of BC patients. Conventional chemotherapeutics, such as docetaxel and paclitaxel, showed greater efficacy in BC patients classified as high-risk. A nomogram with a c-index of 0.764 was developed to forecast the survival time of BC patients, considering their risk score and age. The silencing of C6orf99 markedly decreased the proliferation, migration, and invasion capacities in MCF-7 cells. Our study identified a signature of metabolism-related lncRNAs that predicts outcomes in BC patients and could assist in tailoring personalized prevention and treatment plans.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Idiopathic pulmonary fibrosis (IPF) is a chronic fibrosing interstitial lung disease of unknown etiology that is currently untreatable. In this study we aim to characterize the potential of ...extracellular/circulating microRNAs (miRNAs) in serum as biomarkers for IPF.
Total serum RNAs were isolated from serum from healthy control subjects (n=12), rapid progressive (n=12) and slowly progressive IPF patients (n=12). Serum RNA was analyzed by using TaqMan microRNA assays containing probes for 366 human miRNAs, and selected findings were validated with quantitative RT-PCR. Target prediction and pathway analysis on the significant differential miRNAs were performed using DIANA-mirPath.
We found 47 significantly differentially expressed serum miRNAs (p<0.05) in rapid progressive or slowly progressive IPF patients compared to healthy controls, including 21 up-regulated miRNAs and 26 down-regulated miRNAs. Bioinformatic analysis by DIANA-mirPath demonstrated that 53 KEGG biological processes were significantly enriched (p<0.05, FDR corrected) among differentially expressed serum miRNAs, including TGF-beta signaling pathway (p<0.0001), MAPK signaling pathway (p<0.0001), PI3K–Akt signaling pathway (p<0.0001), Wnt signaling pathway (p<0.0001), HIF-1 signaling pathway (p<0.0001), Regulation of actin cytoskeleton (p<0.0001), Jak–STAT signaling pathway (p<0.0001), Notch signaling pathway (p<0.0001), and Cytokine–cytokine receptor interaction (p=0.0062). We further validated six miRNAs (miR-21, miR-199a-5p, miR-200c, miR-31, let-7a, and let-7d) for further validation using an independent cohort of 20 rapid progressive IPF, 24 slowly progressive IPF patients and 20 healthy controls. In agreement with the preliminary data from miRNA assay, miR-21, miR-199a-5p, and miR-200c were significantly increased in serums of IPF patients while miR-31, let-7a, and let-7d were significantly under expressed in serums of IPF patients compared to healthy controls.
These studies demonstrated that extracellular/circulating miRNAs in serum could be potentially served as novel regulators influencing disease progression of IPF.
•Forty-seven serum miRNAs were differentially expressed in rapid progressive or slowly progressive IPF patients.•TGF-beta, MAPK, PI3K–Akt, and Wnt signaling pathways were significantly enriched among differentially expressed serum miRNAs.•MiR-21, miR-199a-5p, miR-200c, miR-31, let-7a, and let-7d were validated by independent cohorts.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK
Microorganisms have the ability of inhabiting nearly every environment through their sophisticated mechanisms of survival such as biofilm formation and release of outer membrane vesicles (OMVs). The ...biofilm matrix offers microorganism protection and contributes significantly to several clinical challenges, including symptomatic inflammation, antibiotic resistance, recurrence and the spread of infectious emboli. Moreover, bacteria also have another protective mechanism of vesicle production which is used as a means of disseminating toxins to harm their host. A clear understanding of gene expression switch of bacterium from planktonic to biofilm mode offers clinical potentials in treating bacterial infections. In this respect, the treatment of bacterial infections may be achieved through (1) application of RNA interference technology to silence the expression of proteins involved in the process of biofilm formation, (2) utilization of vesicles in delivering antibiotics and (3) use of natural occurred compounds. In this review, we discuss the relationship between biofilm formation and OMV production with respect to tackling biofilm-related clinical challenges. Some prospective considerations in biofilm-associated infections treatment are also discussed.
The relationship between biofilm and outer membrane vesicles.
Twisted bilayer graphene (tBLG) has recently attracted growing interest due to its unique twist-angle-dependent electronic properties. The preparation of high-quality large-area bilayer graphene with ...rich rotation angles would be important for the investigation of angle-dependent physics and applications, which, however, is still challenging. Here, we demonstrate a chemical vapor deposition (CVD) approach for growing high-quality tBLG using a hetero-site nucleation strategy, which enables the nucleation of the second layer at a different site from that of the first layer. The fraction of tBLGs in bilayer graphene domains with twist angles ranging from 0° to 30° was found to be improved to 88%, which is significantly higher than those reported previously. The hetero-site nucleation behavior was carefully investigated using an isotope-labeling technique. Furthermore, the clear Moiré patterns and ultrahigh room-temperature carrier mobility of 68,000 cm
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confirmed the high crystalline quality of our tBLG. Our study opens an avenue for the controllable growth of tBLGs for both fundamental research and practical applications.
Jumonji domain containing protein 2C (JMJD2C) could epigenetically regulate cancer cells. We specifically explored the downstream mechanism of JMJD2C in non-small cell lung cancer (NSCLC) from the ...long non-coding RNA metastasis associated with lung adenocarcinoma transcript 1/microRNA-503-5p/septin 2 (MALAT1/miR-503-5p/SEPT2) axis. NSCLC clinical tissues were utilized to assess JMJD2C, MALAT1, miR-503-5p and SEPT2 levels. NSCLC cell lines (A549 and H1299) were applied for loss-of-function and gain-of-function tests to identify the functional roles of JMJD2C, MALAT1, miR-503-5p, and SEPT2. The interactions among JMJD2C, MALAT1, miR-503-5p, and SEPT2 were assessed. Augmented JMJD2C, MALAT1, and SEPT2 and reduced miR-503-5p levels were found in NSCLC. Depleting JMJD2C or MALAT1, or restoring miR-503-5p exerted anti-tumor effects on NSCLC cells in vitro and in vivo. JMJD2C is bound to the promoter of MALAT1. MALAT1 bound to miR-503-5p and miR-503-5p targeted SEPT2. Knocking down MALAT1 or SEPT2, or elevating miR-503-5p mitigated the pro-tumor effects of upregulated JMJD2C on NSCLC. It is evident that the JMJD2C-mediated MALAT1/miR-503-5p/SEPT2 axis takes part in the process of NSCLC and even worsens NSCLC.
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