2,474 research outputs found

    Review on carbon-derived, solid-state, micro and nano sensors for electrochemical sensing applications

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    The aim of this review is to summarize the most relevant contributions in the development of electrochemical sensors based on carbon materials in the recent years. There have been increasing numbers of reports on the first application of carbon derived materials for the preparation of an electrochemical sensor. These include carbon nanotubes, diamond like carbon films and diamond film-based sensors demonstrating that the particular structure of these carbon material and their unique properties make them a very attractive material for the design of electrochemical biosensors and gas sensors. Carbon nanotubes (CNT) have become one of the most extensively studied nanostructures because of their unique properties. CNT can enhance the electrochemical reactivity of important biomolecules and can promote the electron-transfer reactions of proteins (including those where the redox center is embedded deep within the glycoprotein shell). In addition to enhanced electrochemical reactivity, CNT-modified electrodes have been shown useful to be coated with biomolecules (e.g., nucleic acids) and to alleviate surface fouling effects (such as those involved in the NADH oxidation process). The remarkable sensitivity of CNT conductivity with the surface adsorbates permits the use of CNT as highly sensitive nanoscale sensors. These properties make CNT extremely attractive for a wide range of electrochemical sensors ranging from amperometric enzyme electrodes to DNA hybridization biosensors. Recently, a CNT sensor based fast diagnosis method using non-treated blood assay has been developed for specific detection of hepatitis B virus (HBV) (human liver diseases, such as chronic hepatitis, cirrhosis, and hepatocellular carcinoma caused by hepatitis B virus). The linear detection limits for HBV plasma is in the range 0.5–3.0 μL−1 and for anti- HBVs 0.035–0.242 mg/mL in a 0.1 M NH4H2PO4 electrolyte solution. These detection limits enables early detection of HBV infection in suspected serum samples. Therefore, non-treated blood serum can be directly applied for real-time sensitive detection in medical diagnosis as well as in direct in vivo monitoring. Synthetic diamond has been recognized as an extremely attractive material for both (bio-) chemical sensing and as an interface to biological systems. Synthetic diamond have outstanding electrochemical properties, superior chemical inertness and biocompatibility. Recent advances in the synthesis of highly conducting nanocrystalline-diamond thin films and nano wires have lead to an entirely new class of electrochemical biosensors and bio-inorganic interfaces. In addition, it also combines with development of new chemical approaches to covalently attach biomolecules on the diamond surface also contributed to the advancement of diamond-based biosensors. The feasibility of a capacitive field-effect EDIS (electrolyte-diamond-insulatorsemiconductor) platform for multi-parameter sensing is demonstrated with an O-terminated nanocrystalline-diamond (NCD) film as transducer material for the detection of pH and penicillin concentration. This has also been extended for the label-free electrical monitoring of adsorption and binding of charged macromolecules. One more recent study demonstrated a novel bio-sensing platform, which is introduced by combination of a) geometrically controlled DNA bonding using vertically aligned diamond nano-wires and b) the superior electrochemical sensing properties of diamond as transducer material. Diamond nanowires can be a new approach towards next generation electrochemical gene sensor platforms. This review highlights the advantages of these carbon materials to promote different electron transfer reactions specially those related to biomolecules. Different strategies have been applied for constructing carbon material-based electrochemical sensors, their analytical performance and future prospects are discussed

    The Hopf algebra structure of the Z3_3-graded quantum supergroup GLq,j(1∣1)_{q,j}(1|1)

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    In this work, we give some features of the Z3_3-graded quantum supergroup

    Nanocrystalline diamond film for biosensor applications

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    In this study, we have developed a novel capacitive biosensor based oil interdigitated gold nanodiamond (GID-NCD) electrode for detection of C-reactive protein (CRP) antigen. CRP is one of the plasma proteins known as acute-phase proteins and its levels rise dramatically during inflammatory processes occurring in the body. It has been reported that CRP in serum can be used for risk assessment of cardiovascular diseases. The antibodies immobilization were confirmed by Fourier transform spectroscopy (FTIR) and contact angle measurements. In this capacitive biosensor, nanocrystalline diamond acting as a dielectric layer between the electrodes. The CRP antigen detection was performed by capacitive/dielectric-constant measurements. Our results showed that the response of NCD-based capacitive-based biosensor for CRP antigen was dependent on both concentration (25-800 ng/ml) as well as frequency (50-350 MHz). Furthermore, using optimized conditions, the biosensors developed in this study can be potentially used for detection of elevated level of risk markers protein in suspected subjects for early diagnosis of disease

    A new nanocrystalline diamond-based biosensor for the detection of cardiovascular risk markers

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    In this paper, a new method to probe associative interactions of C-reactive protein (CRP) antigen with CRP antibody immobilized on a gold-interdigitated diamond electrodes was investigated. The CRP antigen detection was performed by capacitive/dielectric-constant measurements. Our results showed that the dynamic detection range using optimized conditions for a given antibody concentration (100 μg/ml) was found to be in the range 25-800 ng/ml of CRP-antigen. Biosensor developed in this study can be potentially used for detection of elevated CRP levels in suspected subjects for early diagnosis

    Automated Data for DevSecOps Programs

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    Symposium PresentationApproved for public release; distribution is unlimited

    Automated Data for DevSecOps Programs

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    Excerpt from the Proceedings of the Nineteenth Annual Acquisition Research SymposiumAutomation in DevSecOps (DSO) transforms the practice of building, deploying, and managing software intensive programs. Although this automation supports continuous delivery and rapid builds, the persistent manual collection of information delays (by weeks) the release of program status metrics and the decisions they are intended to inform. Emerging DSO metrics (e.g., deployment rates, lead times) provide insight into how software development is progressing but fall short of replacing program control metrics for assessing progress (e.g., burn rates against spend targets, integration capability tar-get dates, and schedule for the minimum viable capability release). By instrumenting the (potentially in-teracting) DSO pipelines and supporting environments, the continuous measurement of status, identifica-tion of emerging risks, and probabilistic projections are possible and practical. In this paper, we discuss our research on the information modeling, measurement, metrics, and indicators necessary to establish a continuous program control capability that can keep pace with DSO management needs. We discuss the importance of interactive visualization dashboards for addressing program information needs. We also identify and address the gaps and barriers in the current state of the practice. Finally, we recommend future research needs based on our initial findings.Approved for public release; distribution is unlimited

    Automated Data for DevSecOps Programs

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    Excerpt from the Proceedings of the Nineteenth Annual Acquisition Research SymposiumAutomation in DevSecOps (DSO) transforms the practice of building, deploying, and managing software intensive programs. Although this automation supports continuous delivery and rapid builds, the persistent manual collection of information delays (by weeks) the release of program status metrics and the decisions they are intended to inform. Emerging DSO metrics (e.g., deployment rates, lead times) provide insight into how software development is progressing but fall short of replacing program control metrics for assessing progress (e.g., burn rates against spend targets, integration capability tar-get dates, and schedule for the minimum viable capability release). By instrumenting the (potentially in-teracting) DSO pipelines and supporting environments, the continuous measurement of status, identifica-tion of emerging risks, and probabilistic projections are possible and practical. In this paper, we discuss our research on the information modeling, measurement, metrics, and indicators necessary to establish a continuous program control capability that can keep pace with DSO management needs. We discuss the importance of interactive visualization dashboards for addressing program information needs. We also identify and address the gaps and barriers in the current state of the practice. Finally, we recommend future research needs based on our initial findings.Approved for public release; distribution is unlimited

    High Intensity Interval Training (HIIT) as a Potential Countermeasure for Phenotypic Characteristics of Sarcopenia: A Scoping Review

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    Background: Sarcopenia is defined as a progressive and generalized loss of skeletal muscle quantity and function associated predominantly with aging. Physical activity appears the most promising intervention to attenuate sarcopenia, yet physical activity guidelines are rarely met. In recent years high intensity interval training (HIIT) has garnered interested in athletic populations, clinical populations, and general population alike. There is emerging evidence of the efficacy of HIIT in the young old (i.e. seventh decade of life), yet data concerning the oldest old (i.e., ninth decade of life onwards), and those diagnosed with sarcopenic are sparse. Objectives: In this scoping review of the literature, we aggregated information regarding HIIT as a potential intervention to attenuate phenotypic characteristics of sarcopenia. Eligibility Criteria: Original investigations concerning the impact of HIIT on muscle function, muscle quantity or quality, and physical performance in older individuals (mean age ≥60 years of age) were considered. Sources of Evidence: Five electronic databases (Medline, EMBASE, Web of Science, Scopus, and the Cochrane Central Register of Controlled Trials [CENTRAL]) were searched. Methods: A scoping review was conducted using the Arksey and O'Malley methodological framework (2005). Review selection and characterization were performed by two independent reviewers using pretested forms. Results: Authors reviewed 1,063 titles and abstracts for inclusion with 74 selected for full text review. Thirty-two studies were analyzed. Twenty-seven studies had a mean participant age in the 60s, two in the 70s, and three in the 80s. There were 20 studies which examined the effect of HIIT on muscle function, 22 which examined muscle quantity, and 12 which examined physical performance. HIIT was generally effective in Improving muscle function and physical performance compared to non-exercised controls, moderate intensity continuous training, or pre-HIIT (study design-dependent), with more ambiguity concerning muscle quantity. Conclusions: Most studies presented herein utilized outcome measures defined by the European Working Group on Sarcopenia in Older People (EWGSOP). However, there are too few studies investigating any form of HIIT in the oldest old (i.e., ≥80 years of age), or those already sarcopenic. Therefore, more intervention studies are needed in this population

    Sprint interval training (SIT) reduces serum epidermal growth factor (EGF), but not other inflammatory cytokines in trained older men

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    Purpose The present study aimed to investigate the effect of age on circulating pro- and anti-inflammatory cytokines and growth factors. A secondary aim was to investigate whether a novel sprint interval training (SIT) intervention (3 × 20 s ‘all out’ static sprints, twice a week for 8 weeks) would affect inflammatory markers in older men. Methods Nine older men [68 (1) years] and eleven younger men [28 (2) years] comprised the younger group. Aerobic fitness and inflammatory markers were taken at baseline for both groups and following the SIT intervention for the older group. Results Interleukin (IL)-8, vascular endothelial growth factor (VEGF), and monocyte chemoattractant protein-1 (MCP-1) were unchanged for the older and younger groups at baseline (IL-8, p = 0.819; MCP-1, p = 0.248; VEGF, p = 0.264). Epidermal growth factor (EGF) was greater in the older group compared to the younger group at baseline [142 (20) pg mL−1 and 60 (12) pg mL−1, respectively, p = 0.001, Cohen's d = 1.64]. Following SIT, older men decreased EGF to 100 (12) pg mL−1 which was similar to that of young men who did not undergo training (p = 0.113, Cohen's d = 1.07). Conclusion Older aerobically trained men have greater serum EGF than younger aerobically trained men. A novel SIT intervention in older men can shift circulating EGF towards trained younger concentrations. As lower EGF has previously been associated with longevity in C. elegans, the manipulative effect of SIT on EGF in healthy ageing in the human may be of further interest
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