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161.
Enantiomeric Nanostructures: Chiral Nanostructures from Helical Copolymer–Metal Complexes: Tunable Cation–π Interactions and Sergeants and Soldiers Effect (Small 2/2016) 下载免费PDF全文
162.
In this paper we analyze the monitoring of p Poisson quality characteristics simultaneously, developing a new multivariate control chart based on the linear combination of the Poisson variables, the LCP control chart. The optimization of the coefficients of this linear combination (and control limit) for minimizing the out-of-control ARL is constrained by the desired in-control ARL. In order to facilitate the use of this new control chart the optimization is carried out employing user-friendly Windows© software, which also makes a comparison of performance between this chart and other schemes based on monitoring a set of Poisson variables; namely a control chart on the sum of the variables (MP chart), a control chart on their maximum (MX chart) and an optimized set of univariate Poisson charts (Multiple scheme). The LCP control chart shows very good performance. First, the desired in-control ARL (ARL0) is perfectly matched because the linear combination of Poisson variables is not constrained to integer values, which is an advantage over the rest of charts, which cannot in general match the required ARL0 value. Second, in the vast majority of cases this scheme signals process shifts faster than the rest of the charts. 相似文献
163.
Eduardo González-Ferreiro Ulises Diéguez-Aranda Laura Barreiro-Fernández Sandra Buján Miguel Barbosa Juan C. Suárez 《International journal of remote sensing》2013,34(21):7671-7690
The aim of this study was to evaluate the use of high-resolution airborne laser scanner (ALS) data to detect and measure individual trees. We developed and tested a new mixed pixel- and region-based algorithm (using Definiens Developer 7.0) for locating individual tree positions and estimating their total heights. We computed a canopy height model (CHM) of pixel size 0.25 m from dense first-pulse point data (8 pulses m?2) acquired with a small-footprint discrete-return lidar sensor. We validated the results of individual tree segmentation with accurate field measurements made in 37 plots of Monterey pine (Pinus radiata D. Don) distributed over an area of 36 km2. Fieldwork consisted of labelling all of the trees in each plot and measuring their height and position, for posterior integration of the data from both sources (field and lidar). The proposed algorithm correctly detected and linked 59.8% of the trees in the 37 sample plots. We also manually located the trees by using FUSION software to visualize the raw lidar data cloud. However, because the latter method is extremely time-consuming, we only considered 10 randomly selected plots. Manual location correctly detected and linked 71.9% of the trees (in this subsample the algorithm correctly detected and measured 63.5% of the trees). The R2 values for the linear model relating field- and lidar-measured heights of the linked trees located manually and with the automatic location algorithm were 0.90 and 0.88, respectively. 相似文献
164.
Pressure variations on a train predominantly occur while trains are passing through tunnels. These aerodynamic effects may give rise to aural discomfort in railway passengers. We conducted a field study on the high speed railway track Cologne-Frankfurt/Main as well as a simulation study in our pressure chamber TITAN (DLR-Institute of Aerospace Medicine) with 31 subjects (mean age?=?37.7, SD?=?12.7; 51.6% male) to investigate pressure comfort for passengers. Continuous assessments of pressure events using sliders and retrospective assessments were acquired. Pressure variations were mostly tolerated. A comparison of field and laboratory setting revealed high congruency of continuous as well as retrospective assessments. A generalized estimating equation model identified pressure change attributes contributing to passengers' discomfort. Beside attributes of instantaneous pressure changes (e.g. high amplitudes, short durations), pressure events of the recent past significantly influenced current discomfort. Design engineers may use these findings to improve train and tunnel design. 相似文献
165.
Juan Diego Giraldo Osorio Sandra Gabriela García galiano 《International journal of remote sensing》2013,34(7):2277-2295
Traditional ‘in situ’ measurement techniques often fail to record the spatial distribution of floodplains. In that case, remote sensing provides inexpensive and reliable methodologies to map flooded areas and compute flood damage. The identification and monitoring of floods, due to their highly dynamic nature, require the use of high-time-resolution satellite images with the drawback that such images usually have low to medium spatial resolution. In this context, the traditional classification techniques would not be suitable for delineating floods because they use ‘hard methods’ of classification, where the coarse pixel is assigned to a unique land cover class, generating inaccurate maps of the flooded area. In contrast, the ‘soft methods’ assign several land cover classes within the coarse pixels. In this article, the theoretical basis regarding an innovative methodology of sub-pixel analysis (SA) to identify flooded areas is developed. The improvement in flood delineation is achieved with the use of primary topographic attributes, which stem from a digital elevation model (DEM). The methodology was applied to the monitoring of flood events in the lower Senegal River Valley, using satellite images with moderate spatial resolution. The proposed methodology was demonstrated to be effective for mapping the flood extent: the correct mapping of flooded areas was about 80% in all considered regions, whilst the better performance of supervised classification was 53%. 相似文献
166.
Targeted chemotherapy has become the forefront for cancer treatment in recent years. The selective and specific features allow more effective treatment with reduced side effects. Most targeted therapies, which include small molecules, act on specific molecular targets that are altered in tumour cells, mainly in cancers such as breast, lung, colorectal, lymphoma and leukaemia. With the recent exponential progress in drug development, programmed cell death, which includes apoptosis and autophagy, has become a promising therapeutic target. The research in identifying effective small molecules that target compensatory mechanisms in tumour cells alleviates the emergence of drug resistance. Due to the heterogenous nature of breast cancer, various attempts were made to overcome chemoresistance. Amongst breast cancers, triple negative breast cancer (TNBC) is of particular interest due to its heterogeneous nature in response to chemotherapy. TNBC represents approximately 15% of all breast tumours, however, and still has a poor prognosis. Unlike other breast tumours, signature targets lack for TNBCs, causing high morbidity and mortality. This review highlights several small molecules with promising preclinical data that target autophagy and apoptosis to induce cell death in TNBC cells. 相似文献
167.
Luzia Shundo Adriana P. de Almeida Janete Alaburda Leda C.A. Lamardo Sandra A. Navas Valter Ruvieri Myrna Sabino 《Food Control》2009,20(12):1099-1102
Seventy paprika samples collected in the city of São Paulo, Brazil, from January to April 2006 were analysed for aflatoxins and ochratoxin A (OTA) using an immunoaffinity column clean-up and HPLC-FLD. For aflatoxins, the limit of quantification (LOQ) were 0.23, 0.23, 0.45 and 0.45 μg/kg for AFB1, AFB2, AFG1 and AFG2, respectively. For OTA the LOQ was 0.80 μg/kg. Aflatoxins were found in 82.9% of samples and AFB1 was detected in 61.4% at levels ranging from 0.5 to 7.3 μg/kg with mean concentration of 3.4 μg/kg. OTA was found in 85.7% at levels ranging from 0.24 to 97.2 μg/kg with mean concentration of 7.0 μg/kg. 相似文献
168.
Olivier Guillon Christian Elsässer Oliver Gutfleisch Jürgen Janek Sandra Korte-Kerzel Dierk Raabe Cynthia A. Volkert 《Materials Today》2018,21(5):527-536
The use of external electric and magnetic fields for the synthesis and processing of inorganic materials such as metals and ceramics has seen renewed interest in recent years. Electromagnetic energy can be utilized in different ways to improve or accelerate phase formation and stabilization, chemical ordering, densification and coarsening of particle-based materials (pore elimination and grain growth), and mechanical deformation (plasticity and creep). In these new synthesis and processing routes, the resulting microstructures and macroscopic material behavior are determined by the interaction of the applied fields with defects such as single or clustered point defects, dislocation networks, and interfaces. Multiscale experimental investigations and modeling are necessary to unveil the mechanisms underlying this field-assisted manipulation of matter. 相似文献
169.
Vadym Burchak Fritz Koch Leonard Siebler Sonja Haase Verena K. Horner Xenia Kempter G. Bjrn Stark Ute Schepers Alisa Grimm Stefan Zimmermann Peter Koltay Sandra Strassburg Günter Finkenzeller Filip Simunovic Florian Lampert 《International journal of molecular sciences》2022,23(14)
Introduction: Three-dimensional bioprinting can be considered as an advancement of the classical tissue engineering concept. For bioprinting, cells have to be dispersed in hydrogels. Recently, a novel semi-synthetic thiolene hydrogel system based on norbornene-functionalized gelatin (GelNB) and thiolated gelatin (GelS) was described that resulted in the photoclick hydrogel GelNB/GelS. In this study, we evaluated the printability and biocompatibility of this hydrogel system towards adipose-tissue-derived mesenchymal stem cells (ASCs). Methods: GelNB/GelS was synthesized with three different crosslinking densities (low, medium and high), resulting in different mechanical properties with moduli of elasticity between 206 Pa and 1383 Pa. These hydrogels were tested for their biocompatibility towards ASCs in terms of their viability, proliferation and differentiation. The extrusion-based bioprinting of ASCs in GelNB/GelS-high was performed to manufacture three-dimensional cubic constructs. Results: All three hydrogels supported the viability, proliferation and chondrogenic differentiation of ASCs to a similar extent. The adipogenic differentiation of ASCs was better supported by the softer hydrogel (GelNB/GelS-low), whereas the osteogenic differentiation was more pronounced in the harder hydrogel (GelNB/GelS-high), indicating that the differentiation fate of ASCs can be influenced via the adaption of the mechanical properties of the GelNB/GelS system. After the ex vivo chondrogenic differentiation and subcutaneous implantation of the bioprinted construct into immunocompromised mice, the production of negatively charged sulfated proteoglycans could be observed with only minimal inflammatory signs in the implanted material. Conclusions: Our results indicate that the GelNB/GelS hydrogels are very well suited for the bioprinting of ASCs and may represent attractive hydrogels for subsequent in vivo tissue engineering applications. 相似文献
170.
Beghi SP Santos JM Reis NC de Sá LM Goulart EV de Abreu Costa E 《Water science and technology》2012,66(10):2223-2228
Complaints from the Domingos Martins population about sewage odours in the city made the district attorney order an impact assessment of the odours emitted by the city wastewater treatment plant (WWTP). This study comprised various techniques, models and population surveys. In 2007, an odour emission model proved that the main hydrogen sulphide emitter was the aeration tank of the WWTP (13.5 g h(-1)) and such emissions, according to CALPUFF model, should be perceived in the whole Domingos Martins city centre area. In this area, 58% of those interviewed were annoyed by the WWTP odours. However, in 2009, the odour monitoring panel recorded few odour occurrences. A second population survey showed that hereafter only 20% of those interviewed were annoyed by the WWTP emissions. Odour emission and dispersion models run with 2010 data proved a drastic reduction of the WWTP aeration tank emissions and consequently the city centre was not bothered by WWTP emissions anymore. The odour emission reduction was due to the modification of the WWTP aeration tank system. Despite the odour emission reduction, houses located southeast of the WWTP were still annoyed by sewage odours. However, in this part of the town, other sources of sewage odours have been found. 相似文献