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51.
The role of the synaptic vesicle protein 2A (SV2A) protein, target of the antiepileptic drug levetiracetam, is still mostly unknown. Considering its potential to provide in vivo functional insights into the role of SV2A in epileptic patients, the development of an SV2A positron emission tomography (PET) tracer has been undertaken. Using a 3D pharmacophore model based on close analogues of levetiracetam, we report the rationale design of three heterocyclic non‐acetamide lead compounds, UCB‐A, UCB‐H and UCB‐J, the first single‐digit nanomolar SV2A ligands with suitable properties for development as PET tracers.  相似文献   
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Software Product Lines (SPL) are difficult to validate due to combinatorics induced by variability, which in turn leads to combinatorial explosion of the number of derivable products. Exhaustive testing in such a large products space is hardly feasible. Hence, one possible option is to test SPLs by generating test configurations that cover all possible t feature interactions (t-wise). It dramatically reduces the number of test products while ensuring reasonable SPL coverage. In this paper, we report our experience on applying t-wise techniques for SPL with two independent toolsets developed by the authors. One focuses on generality and splits the generation problem according to strategies. The other emphasizes providing efficient generation. To evaluate the respective merits of the approaches, measures such as the number of generated test configurations and the similarity between them are provided. By applying these measures, we were able to derive useful insights for pairwise and t-wise testing of product lines.  相似文献   
54.
In the forest industry, bark is an abundant residue, predominantly converted into calorific energy. As the antioxidant potential of phenolic compounds from sugar maple (Acer saccharum Marsh.) and red maple (Acer rubrum L.) bark has previously been established, the present study focused on the hot-water extraction optimization of these barks. Several process parameters (maple species, temperature, duration, ratio bark/water, particle size) were thus studied and large disparities were found between the two species. Extraction yield, phenolic content, and antioxidant capacity of red maple extracts were several times higher than those of sugar maple extracts. Principal component analysis, applied to the selected best extraction conditions, identified 3–4 clusters depending on the maple species. These groups were sorted from the highest extraction yield and energy consumption combined with the lowest phenolic content and antioxidant capacity, to moderate extraction yield and energy consumption with the highest phenolic content and antioxidant capacity.  相似文献   
55.
Typically, 15–45% of the mixed liquor (sludge) in biological wastewater treatment plants (WWTPs) consists of inorganic (fixed) suspended solids. A portion of these inorganic compounds is grit (sand) originating from the influent. Grit accumulation impacts WWTP design and operating costs as these unbiodegradable solids reduce the effective treatment capacity of the bioreactor and other unit operations that must be sized to carry this material.The goal of this study was to characterize the performance of a hydrocyclone to selectively separate grit from activated sludge. Laboratory experiments were conducted with a 13 mm diameter Krebs hydrocyclone treating sludge from eight WWTPs. Reduced efficiencies of 17 ± 7% on fixed suspended solids and 9 ± 6% on volatile suspended solids were obtained. Grade efficiency curves enabled the development of a modified definition for cut size useful for this application. The characterization of hydrocyclone performance for grit removal from activated sludge will enable modelling of the process for integration into wastewater treatment simulators used for process performance prediction and design.  相似文献   
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A novel process concept for the oxidative coupling of methane followed by the oligomerization to liquids has been developed within the frame of the EU integrated project OCMOL. This technology is based on process intensification principles via cutting‐edge structured microreactor technology. It is also a fully integrated industrial process through the re‐use and the recycling of by‐products, in particular CO2, at every process stage. The focus of this contribution is on the reaction engineering aspects of the core steps, i.e., catalysts, kinetics and reactor design for the methane coupling and reforming.  相似文献   
58.
Tensile properties and crack propagation properties, especially critical strain energy release rate in mode I, GIC, have been used to investigate fracture properties of elastomers and their relationships with microstructure. These investigations were mainly based on a series of comparisons: first, the behaviour of polychloroprene rubber (CR), undergoing stress hardening due to strain induced crystallization (SIC) and oxidative crosslinking (OCL) was compared with that of chlorinated polyethylene (CPE), which undergoes SIC but not OCL, and with a polyurethane based on hydroxyl terminated polybutadiene (PU) which undergoes OCL but not SIC. Comparisons were also made on CR between fracture behaviour at ambient temperature, where SIC occurs and at 100 °C where there is no SIC. Finally, oxidative crosslinking was used to vary in a continuous way the crosslink density in CR and PU, in order to evaluate the role of crosslinking in fracture behaviour.  相似文献   
59.
α-Actinin release and its degradation from myofibrils Z-line were studied in post mortem white dorsal muscle from bass and sea trout stored at 4°C and 10°C. Using α-actinin specific antibodies, we show that this protein is rapidly released within the first 24 h for the two species, and reaches a plateau within 4 days. Proteolysis take place very rapidly in bass muscle yielding 80 and 40 kDa fragments from α-actinin as major bands of proteolysis. Sea trout muscle is more resistant, and muscle stored at 4°C is not significantly α-actinin degraded even 10 days after death. In the case of sea trout muscle stored at 10°C, an increasing quantity of 80 and 40 kDa fragment can be observed after the third day. These results show that release and proteolysis of α-actinin are time- and temperature-dependent processes that take place at the early stages of fish storage. Furthermore, we observed that proteolysis of α-actinin seems to be dependent on fish species. In both species studied, the early release of α-actinin comes before the degradation of released molecules, and appears as a biphasic process throughout the disorganisation of post mortem muscle in fish cold-stored above 0°C.  相似文献   
60.
The composition of various commercial tannin extracts were determined by liquid secondary ion mass spectrometry (LSIMS). Spectra were obtained directly from tannin extracts without any pre-separation. Eight different tannin powders were analysed: three gallotannins (Chinese, Turkish, tara), three ellagitannins (sweet chestnut, pendunculata oak, sessile oak), one mixed hydrolysable tannin (myrabolans) and one proanthocyanidin (grape seeds). This method enabled the main molecules in these powders to be identified.  相似文献   
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