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71.
Technological premises for a successful economical path toward low carbon economy are described. It is attempted to relate fossil fuels (lignite) combustion with the requirements for sustainable energy production in Greece proposing economic, feasible and environmentally friendly methods for minimization of the CO2 problem using innovative techniques for separation, carbon capture and storage (CCS) of this greenhouse gas. CCS constitutes an intermediate perspective to a low carbon energy production. Inexpensive and efficient methods of CCS can be achieved by new physicochemical methodologies enhancing the adsorption driven carbon dioxide capture in zeolite voids or in depleted lignite matrices, eventually by exploitation existing natural Greek deposits. The large scale application of a recently developed method leading to a high CO2-over-N2 selectivity and adsorption capacity NaKA Zeolite is examined.  相似文献   
72.
Applications targeting smart cities tackle common challenges, however solutions are seldom portable from one city to another due to the heterogeneity of smart city ecosystems. A major obstacle involves the differences in the levels of available information. In this work, we present REMI, which is a mining framework that handles varying degrees of information availability by providing a meta-solution to missing data. The framework core concept is the REMI layered stack architecture, offering two complementary approaches to dealing with missing information, namely data enrichment (DARE) and graceful degradation (GRADE). DARE aims at inference of missing information levels, while GRADE attempts to mine the patterns using only the existing data.We show that REMI provides multiple ways for re-usability, while being fault tolerant and enabling incremental development. One may apply the architecture to different problem instantiations within the same domain, or deploy it across various domains. Furthermore, we introduce the other three components of the REMI framework backing the layered stack. To support decision making in this framework, we show a mapping of REMI into an optimization problem (OTP) that balances the trade-off between three costs: inaccuracies in inference of missing data (DARE), errors when using less information (GRADE), and gathering of additional data. Further, we provide an experimental evaluation of REMI using real-world transportation data coming from two European smart cities, namely Dublin and Warsaw.  相似文献   
73.
Behavioral genetic investigations have consistently demonstrated large genetic influences for the core symptom dimensions of attention-deficit/hyperactivity disorder (ADHD), namely inattention (INATT) and hyperactivity (HYP). Yet little is known regarding potential similarities and differences in the type of genetic influence (i.e., additive vs. nonadditive) on INATT and HYP. As these symptom dimensions form the basis of the current Diagnostic and Statistical Manual of Mental Disorders subtype classification system, evidence of differential genetic influences would have important implications for research investigating causal mechanisms for ADHD. The current meta-analysis aimed to investigate the nature of etiological influences for INATT and HYP by comparing the type and magnitude of genetic and environmental influences each. A comprehensive literature search yielded 79 twin and adoption studies of INATT and/or HYP. Of these, 13 samples of INATT and 9 samples of HYP were retained for analysis. Results indicated that both dimensions were highly heritable (genetic factors accounted for 71% and 73% of the variance in INATT and HYP, respectively). However, the 2 dimensions were distinct as to the type of genetic influence. Dominant genetic effects were significantly larger for INATT than for HYP, whereas additive genetic effects were larger for HYP than for INATT. Estimates of unique environmental effects were small to moderate and shared environmental effects were negligible for both symptom dimensions. The pattern of results generally persisted across several moderating factors, including gender, age, informant, and measurement method. These findings highlight the need for future studies to disambiguate INATT and HYP when investigating the causal mechanisms, and particularly genetic influences, behind ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
    
Colorectal cancer represents a leading cause of cancer-related morbidity and mortality. Despite improvements, chemotherapy remains the backbone of colorectal cancer treatment. The aim of this study is to investigate the variation of circulating microRNA expression profiles and the response to irinotecan-based treatment in metastatic colorectal cancer and to identify relevant target genes and molecular functions. Serum samples from 95 metastatic colorectal cancer patients were analyzed. The microRNA expression was tested with a NucleoSpin miRNA kit (Machnery-Nagel, Germany), and a machine learning approach was subsequently applied for microRNA profiling. The top 10 upregulated microRNAs in the non-responders group were hsa-miR-181b-5p, hsa-miR-10b-5p, hsa-let-7f-5p, hsa-miR-181a-5p, hsa-miR-181d-5p, hsa-miR-301a-3p, hsa-miR-92a-3p, hsa-miR-155-5p, hsa-miR-30c-5p, and hsa-let-7i-5p. Similarly, the top 10 downregulated microRNAs were hsa-let-7d-5p, hsa-let-7c-5p, hsa-miR-215-5p, hsa-miR-143-3p, hsa-let-7a-5p, hsa-miR-10a-5p, hsa-miR-142-5p, hsa-miR-148a-3p, hsa-miR-122-5p, and hsa-miR-17-5p. The upregulation of microRNAs in the miR-181 family and the downregulation of those in the let-7 family appear to be mostly involved with non-responsiveness to irinotecan-based treatment.  相似文献   
75.
    
Langmuir–Blodgett (LB) film deposition gives an opportunity to control the packing density and orientation of anisotropic nanoparticles at a monolayer level, allowing accurate characterization of their anisotropic material properties. The uniaxial deposition of rod‐shaped cellulose nanocrystals (CNCs) over a macroscopically large area is achieved by aligning the long axis of CNCs on the LB trough with the direction of the maximum drag force within the meniscus during the vertical pulling of the substrate from the LB trough. On the uniaxially‐aligned LB films, anisotropic linear and non‐linear optical properties of CNCs are obtained using Mueller matrix spectroscopy and sum frequency generation spectroscopy, respectively, and explained with time‐dependent density functional theory calculations. Also, the frictional anisotropy of the LB film is measured using atomic force microscopy and explained theoretically. The findings of this study will be valuable for preparation of anisotropic nanoparticle thin films with uniform arrangements and utilization of their anisotropic material properties.  相似文献   
76.
    
High‐resolution RGB organic light‐emitting diode frontplane is a key enabler for direct‐view transparent augmented reality displays. In this paper, we demonstrate 1250 ppi passive displays and semi‐transparent active displays. Organic light‐emitting diode photolithography can provide pixel density above 1000 ppi while keeping effective emission area high because of high aperture ratio. Patterns with 2 μm line pitch were successfully transferred to emission layers, indicating possible further pixel density scaling. Lifetime after patterning, key parameter enabling industrialization, is above 150 h (T90 at 1000 nit).  相似文献   
77.
    
Drill & blast and special foundation in Gothenburg Growing economies and populations in the Gothenburg metropolitan area make infrastructure measures inevitable for Sweden's second largest city. As a sub‐project of The West Swedish Agreement, which also includes the construction of the Marienholm Tunnel and the new Hising Bridge, a new railway line for commuter and regional trains will be built as part of the “Gothenburg West Link” (Gothenburg Västlänken) and is expected to go into operation in 2026. In addition to the two new stations Haga and Korsvägen, the existing station Centralen will be extended by the 8 km long infrastructure project. The three stations are located in loose rock areas consisting of varved clay, glacial deposits and moraines, while 6 km of the line will be tunneled through Swedish metabasite, gneiss and pegmatite. The client is the Swedish transport administration Trafikverket. This report focuses on the construction and case record of the project unit Korsvägen, which was won by the bidding community consisting of the Swedish construction company NCC and the German BAM subsidiary Wayss & Freytag Ingenieurbau AG. This article also provides insight into the application of the BIM method and other digitization approaches for process optimization.  相似文献   
78.
79.
Complex dielectric functions of anodic bi-layer tantalum oxide   总被引:1,自引:0,他引:1  
The optical properties and structure of anodic oxides are dependent on the anodization conditions. For tantalum oxide formed in dilute phosphoric acid, the anodic oxide forms as two chemically distinct layers, referred to as a bi-layer, where the inner layer is pure tantalum oxide and the outer layer contains incorporated phosphate. The complex dielectric functions of the individual inner and outer layers are determined using spectroscopic ellipsometry. The dielectric functions of the bi-layers are compared to mono-layer oxides formed in sodium sulfate, and the effects of hydrothermal sealing are explored. For bi-layer oxides formed to 70 V in phosphoric acid, the inner layer band gap is 4.37 ± 0.02 eV and the outer layer band gap is 3.86 ± 0.06 eV. Thin anodic oxides (∼6-15 nm) are best described by a mono-layer oxide model and exhibit higher optical absorption with a band gap of 3.98 ± 0.08 eV. This study shows that spectroscopic ellipsometry is a valuable tool in assessing processing-property relationships of multi-layer anodic films.  相似文献   
80.
Despite sequence similarity to SARS-CoV-1, SARS-CoV-2 has demonstrated greater widespread virulence and unique challenges to researchers aiming to study its pathogenicity in humans. The interaction of the viral receptor binding domain (RBD) with its main host cell receptor, angiotensin-converting enzyme 2 (ACE2), has emerged as a critical focal point for the development of anti-viral therapeutics and vaccines. In this study, we selectively identify and characterize the impact of mutating certain amino acid residues in the RBD of SARS-CoV-2 and in ACE2, by utilizing our recently developed NanoBiT technology-based biosensor as well as pseudotyped-virus infectivity assays. Specifically, we examine the mutational effects on RBD-ACE2 binding ability, efficacy of competitive inhibitors, as well as neutralizing antibody activity. We also look at the implications the mutations may have on virus transmissibility, host susceptibility, and the virus transmission path to humans. These critical determinants of virus–host interactions may provide more effective targets for ongoing vaccines, drug development, and potentially pave the way for determining the genetic variation underlying disease severity.  相似文献   
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