453 research outputs found
Redox properties of alkyl-substituted 4-aryl-2,4-dioxobutanoic acids
© 2017 J. Serb. Chem. Soc. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (https://creativecommons.org/licenses/by-nc-nd/4.0/).Redox properties of a set of aryldiketo acids (ADKs), small organic molecules that comprise 2,4-dioxobutanoic acid moiety, were studied. Along with well-known HIV-1 integrase (IN) inhibition, ADKs exert widespread biological activities. The aim of this work was to evaluate effects of aryl substitutions on properties of dioxobutanoic moiety that is involved in key interactions with metal ions within active sites of target enzymes. The effect of pH on electronic properties of nine congeners was examined using cyclic voltammetry and differential pulse polarography. Compounds were chosen as a simple set of congeners, bearing Me-groups on phenyl ring which should not be involved in electrochemical reactions, leaving diketo moiety as sole electrophore. Substitution pattern was systematically varied, yielding a set having different torsion between phenyl ring and aryl keto group (Ar-C(O)). Protonation state of ADKs at different pH values was determined from experimentally obtained pKas. The results showed that the equal number of protons and electrons is involved in the oxidation and reduction reactions at the surface of electrode. Quantitative linear correlations between reduction potentials and energies of frontier orbitals, calculated for neutral, monoanionic and corresponding radical anionic species, and steric parameter were found.Peer reviewe
Influence of Cellulose on the Anoxic Treatment of Domestic Wastewater in Septic Tanks: Statistical Analysis of the Chemical and Physico-Chemical Parameters
Cellulose is a very common polymer in domestic wastewater (WW), representing a not negligible part of the organic substance contained in sewage. To date, many studies have highlighted the feasibility of reusing this compound in several ways (e.g., building sector, wastewater treatment, energy production, etc.) after its separation from domestic WW. However, studies about the impact of the absence of cellulose on the chemical and physico-chemical parameters of a biological process are still lacking. In this work, two pilot-scale plants were used to simulate an anoxic treatment of WW in septic tanks, with and without cellulose (CWW and NCWW, respectively), for three months. The results of the monitoring highlighted that T, pH, and electrical conductivity (EC) remained almost constants, in both cases. The Spearman correlation coefficients (SCC) for turbidity (TUR), total suspended solids (TSS), and color (COL) indicated a higher removal in the case of CWW (65%, 66%, and 56%, respectively). Organic substance and nitrogen forms showed a similar behavior with and without cellulose, but in the case of CWW, N-NH3 was highly negatively correlated with TUR (SCC: −0.54), TSS (−0.49), and COL (−0.39). A biological denitrification process was highlighted in both cases. Despite these differences, when statistically analyzing the trends of the chemical and physico-chemical parameters for CWW and NCWW, a significant difference due to the absence of cellulose was excluded. These results will be useful to the scientific community, as they exclude that the operational parameters of anoxic treatments and the effectiveness on pollutants removal can be affected in the case of preliminary cellulose separation from domestic WW for recovery/reuse purposes
Cell autonomous and noncell-autonomous role of NF-\u3baB p50 in astrocyte-mediated fate specification of adult neural progenitor cells.
Lifestyle characteristics influencing hypertension in middle-age to old people: comparison of two populations
Background: Hypertension is a significant global public health problem and the data suggest a wide health disparity in hypertension prevalence worldwide. Our objective was to assess some epidemiological determinants in individuals ≥ 50 years influencing blood pressure/hypertension in United States and Croatia and derive some meaningful conclusions and recommendations. Material and methods: We used the American National Health and Nutrition Examination Survey (NHANES) (n = 1,556; 48.9% women) and the Croatian Adult Health Cohort Study (CroHort) (n = 2,182; 66% women), both taken in 2008. The health indicators compared were anthropometries, blood pressure, socioeconomic and marital status, education and lifestyle, including physical activity, alcohol and coffee consumption, smoking and presence of dyslipidemia and diabetes. Results: Prevalence of hypertension based either on medication use or blood pressure values was significantly higher in Croatian men and women compared to American (all p < 0.001). Waist circumference was the main positive predictor and education a negative predictor for blood pressure in CroHort; significance was not reached in NHANES, although the trends were similar. Taking medications for diabetes decreased the odds for hypertension in NHANES, while taking medications for both diabetes and dyslipidemia decreased the odds in CroHort. Conclusions: Croatian people older than 50 years have higher prevalence of hypertension compared to their counterparts in the U.S. The difference in the prevalence of hypertension in two populations cannot be explained by different prevalence of risk factors examined, except education level. Higher prevalence of hypertension diagnosed by medication use indicates a relatively good control of the disease in both populations
Progenitors of distinct lineages shape the diversity of mature type 2 conventional dendritic cells
Conventional dendritic cells (cDC) are antigen-presenting cells comprising cDC1 and cDC2, responsible for priming naive CD
Transmission of OFDM wired-wireless quintuple-play services along WDM LR-PONs using centralized broadband impairment compensation
This paper was published in OPTICS EXPRESS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OE.20.013748 . Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law[EN] The simultaneous transmission of four orthogonal frequencydivision multiplexing (OFDM)-based signals used to provide quintuple-play services along wavelength division multiplexing (WDM) long-reach passive optical networks (LR-PONs) is demonstrated experimentally. Particularly, the transmission performance of custom signal bearing Gigabit Ethernet data, Worldwide Interoperability for Microwave Access, Long Term Evolution and Ultra Wideband (sub-bands 2 and 3) signals is evaluated for different LR-PONs reaches, considering single-wavelength andWDMtransmission, and using a centralized impairment compensation technique at the central office that is transparent to the services provided. It is shown that error vector magnitude-compliant levels are obtained for all the OFDM-based signals in WDM LR-PONs reaching 100 km and that negligible inter-channel crosstalk is obtained for a channel spacing of 100 GHz regardless the OFDM-based signal considered. The successful multi-format OFDM transmission along the 100 km-long WDM LR-PON is achieved in the absence of optical dispersion compensation or single sideband modulation, and it is enabled by the performance improvement provided by the centralized impairment compensation realized. © 2012 Optical Society of America.M. Morant's work was supported by FPU-MEC grant AP2007-01413. This work was also supported in part by the European FIVER-FP7-ICT-2009-4-249142 project and by Fundacao para a Ciencia e a Tecnologia from Portugal under the TURBO-PTDC/EEA-TEL/104358/2008 project.Alves, T.; Morant Pérez, M.; Cartaxo, A.; Llorente Sáez, R. (2012). Transmission of OFDM wired-wireless quintuple-play services along WDM LR-PONs using centralized broadband impairment compensation. Optics Express. 20(13):13748-13761. https://doi.org/10.1364/OE.20.013748S13748137612013Jia, Z., Yu, J., Ellinas, G., & Chang, G.-K. (2007). Key Enabling Technologies for Optical–Wireless Networks: Optical Millimeter-Wave Generation, Wavelength Reuse, and Architecture. Journal of Lightwave Technology, 25(11), 3452-3471. doi:10.1109/jlt.2007.909201Armstrong, J. (2009). OFDM for Optical Communications. Journal of Lightwave Technology, 27(3), 189-204. doi:10.1109/jlt.2008.2010061Cvijetic, N. (2012). OFDM for Next-Generation Optical Access Networks. Journal of Lightwave Technology, 30(4), 384-398. doi:10.1109/jlt.2011.2166375Shieh, W., & Athaudage, C. (2006). Coherent optical orthogonal frequency division multiplexing. Electronics Letters, 42(10), 587. doi:10.1049/el:20060561Alves, T., Morant, M., Cartaxo, A., & Llorente, R. (2011). Performance Comparison of OFDM-UWB Radio Signals Distribution in Long-Reach PONs Using Mach-Zehnder and Linearized Modulators. IEEE Journal on Selected Areas in Communications, 29(6), 1311-1320. doi:10.1109/jsac.2011.110618Llorente, R., Alves, T., Morant, M., Beltran, M., Perez, J., Cartaxo, A., & Marti, J. (2008). Ultra-Wideband Radio Signals Distribution in FTTH Networks. IEEE Photonics Technology Letters, 20(11), 945-947. doi:10.1109/lpt.2008.922329Alves, T., & Cartaxo, A. (2011). Distribution of Double-Sideband OFDM-UWB Radio Signals in Dispersion Compensated Long-Reach PONs. Journal of Lightwave Technology, 29(16), 2467-2474. doi:10.1109/jlt.2011.2160616Chow, C.-W., Yeh, C.-H., Wang, C.-H., Shih, F.-Y., Pan, C.-L., & Chi, S. (2008). WDM extended reach passive optical networks using OFDM-QAM. Optics Express, 16(16), 12096. doi:10.1364/oe.16.012096Tang, J. M., Lane, P. M., & Shore, K. A. (2006). Transmission performance of adaptively modulated optical OFDM signals in multimode fiber links. IEEE Photonics Technology Letters, 18(1), 205-207. doi:10.1109/lpt.2005.861631Duong, T.-N., Genay, N., Ouzzif, M., Le Masson, J., Charbonnier, B., Chanclou, P., & Simon, J. C. (2009). Adaptive Loading Algorithm Implemented in AMOOFDM for NG-PON System Integrating Cost-Effective and Low-Bandwidth Optical Devices. IEEE Photonics Technology Letters, 21(12), 790-792. doi:10.1109/lpt.2009.2016978Alves, T., & Cartaxo, A. (2009). Performance Degradation Due to OFDM-UWB Radio Signal Transmission Along Dispersive Single-Mode Fiber. IEEE Photonics Technology Letters, 21(3), 158-160. doi:10.1109/lpt.2008.200923
Surface-based GPU-friendly geometry modeling for detector simulation
In a context where the high-energy physics community strives to enhance software to handle increased data throughput, detector simulation is evolving to take advantage of new performance opportunities. Given the intricacy of particle transport simulation, recent advancements, such as adapting to accelerator hardware, require a significant research and development effort.
The feasibility of porting complex particle transport codes to GPUs has been already demonstrated by parallelizing the processing of tracks undergoing electromagnetic interactions. However, the GPU workflow presents distinct performance bottlenecks compared to the CPU workflow, owing to differences in parallelism models and hardware capabilities. Notably, the geometry component in this workflow has emerged as the primary bottleneck that needs addressing to enhance GPU-based simulations. The current CUDA-aware geometry is a 3D-solid modeler featuring substantial warp divergence, primarily due to the varying complexity of the supported 3D primitive solid shapes.
We present the outcomes of a one-year endeavor to create a bounded surface model that can seamlessly map the navigation capabilities of the existing solidbased geometry, with a focus on improving GPU efficiency. Our implementation aims to simplify low-level algorithms to reduce warp divergence, while simultaneously eliminating other sources of GPU inefficiency, such as recursive and virtual function calls, and ensuring code portability
Is it necessary to innovate in agriculture to maintain competitiveness?
Bacheloroppgave i økonomi og administrasjon, Høgskulen på Vestlandet, campus BergenØMF19
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