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81.
This paper describes a hybrid tabu search algorithm dedicated to a job shop problem with a no-wait constraint with a makespan criterion. The proposed here algorithm complexity is that the superior algorithm based on the tabu search technique selects parameters controlling the work of a certain constructional algorithm. This approach limits the checked solutions only to a group of solutions being able to be generated by the structural algorithm in question. It bears serious consequences both positive, for example it limits the research scope for a small fraction of relatively extremely well quality of acceptable solutions, and negative that is the lack of possibility of finding the optimal solution. In this paper numerical researches of the proposed algorithm are conducted as well as a comparative analysis with reference to the literature algorithms of the algorithm in question is made.  相似文献   
82.
The effects on the aroma compositions of ethanol extracts obtained by traditional and enzyme‐assisted methods from seven killing conditions used in vanilla pod curing were studied. Two procedures of vanilla pod killing consisted of either freezing pods at ?10 °C for 24 h or immersing pods in 80 °C water for 10 s each of three times with 30 s intervals resulted in the highest vanillin values in terms percentage of dry weight of the bean (2.84 and 2.96), 4‐hydroxybenzaldehyde (0.18 and 0.20), vanillyl alcohol (0.56 and 0.57) and vanillic acid (0.18 and 0.19 respectively) when traditional vanilla ethanol extraction was used. When this extract was aged for 3 months it showed improvement in flavour compounds. Enzyme‐assisted vanilla ethanol extraction showed a higher content of flavour compounds than traditional extract, for example vanillin 4.38% and 2.96% respectively. Only vanillic acid levels were improved after ageing of the enzyme‐assisted extracts.  相似文献   
83.
Cancer is a leading cause of death worldwide. In many cases, the treatment of the disease is limited due to the metastasis of cells to distant locations of the body through the blood and lymphatic drainage. Most of the anticancer therapeutic options focus mainly on the inhibition of tumor cell growth or the induction of cell death, and do not consider the molecular basis of metastasis. The aim of this work is to provide a comprehensive review focusing on cancer metastasis and the mitogen-activated protein kinase (MAPK) pathway (ERK/JNK/P38 signaling) as a crucial modulator of this process.  相似文献   
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85.
During a stroke, a series of biochemical and metabolic changes occur which eventually lead to the death of cells by necrosis or apoptosis. This is a multi-stage process involving oxidative stress and an inflammatory response from the first signs of occlusion of a blood vessel until the late stages of regeneration and healing of ischemic tissues. The purpose of the research was to assess the concentration of pro-inflammatory cytokines IL-6 and TNF-α in the blood serum of patients with ischemic stroke (AIS) and to investigate their role as new markers in predicting functional prognosis after thrombolytic therapy. The researches have shown that the concentrations of the measured biomarkers were higher compared to the control group. Serum levels of IL-6 and THF-α before the initiation of intravenous thrombolysis were lower in the subgroup of patients with a favourable functional result (mRS: 0–2 pts) compared to the group of patients with an unfavourable functional result (mRS: 3–6 pts). A positive correlation was found between the concentration of IL-6 and TNF-α in patients with AIS during <4.5 h and on one day after the onset of stroke, which means that the concentration of IL-6 increases with the increase in TNF-α concentration. It has also been shown that higher levels of IL-6 in the acute phase of stroke and on the first and seventh days, and TNF-α during onset, were associated with poorer early and late prognosis in patients treated with intravenous thrombolysis. A relationship was found between the level of IL-6 and TNF-α in the subacute AIS and the severity of the neurological deficit. It has been shown that the investigated biomarkers may be a prognostic factor in the treatment of thrombolytic AIS.  相似文献   
86.
87.
The effect of the interaction between fullerenol C60(OH)36 (FUL) and alcohol dehydrogenase (ADH) from Saccharomyces cerevisiae and human serum albumin (HSA) was studied by absorption spectroscopy, fluorescence spectroscopy, and time-resolved fluorescence spectroscopy. As shown in the study, the fluorescence intensities of ADH and HSA at excitation wavelengths λex = 280 nm (Trp, Tyr) and λex = 295 nm (Trp) are decreased with the increase in the FUL concentration. The results of time-resolved measurements indicate that both quenching mechanisms, dynamic and static, are present. The binding constant Kb and the number of binding sites were obtained for HSA and ADH. Thus, the results indicated the formation of FUL complexes and proteins. However, the binding of FUL to HSA is much stronger than that of ADH. The transfer of energy from the protein to FUL was also proved.  相似文献   
88.
This article presents the results of structural tests of composite coatings on a NiSi2B alloy matrix containing carbides of Ti and Cr, which have been plasma surfaced from a powder mixture onto a low-alloyed steel substrate. The content and distribution of the strengthening phase in the matrix have been determined. It has been shown that the different nature of the interaction between Ti and Cr carbides and the liquid Ni alloy significantly affects the formation of composite surfacing layers as well as the distribution and content of strengthening phase particles in the matrix.  相似文献   
89.
This is the first study in which the Daphnia magna (D. magna) nuclear genome (nDNA) obtained from the GenBank database was analyzed for pseudogene sequences of mitochondrial origin. To date, there is no information about pseudogenes localized in D. magna genome. This study aimed to identify NUMTs, their length, homology, and location for potential use in evolutionary studies and to check whether their occurrence causes co-amplification during mitochondrial genome (mtDNA) analyses. Bioinformatic analysis showed 1909 fragments of the mtDNA of D. magna, of which 1630 were located in ten linkage groups (LG) of the nDNA. The best-matched NUMTs covering >90% of the gene sequence have been identified for two mt-tRNA genes, and they may be functional nuclear RNA molecules. Isolating the total DNA in mtDNA studies, co-amplification of nDNA fragments is unlikely in the case of amplification of the whole tRNA genes as well as fragments of other genes. It was observed that TRNA-MET fragments had the highest level of sequence homology, thus they could be evolutionarily the youngest. The lowest homology was found in the D-loop-derived pseudogene. It may probably be the oldest NUMT incorporated into the nDNA; however, further analysis is necessary.  相似文献   
90.
This paper describes variations in whisker growth on the surface of tin-rich, lead-free alloys soldered on a Cu layer depending on the laminate used for the printed circuit board, which can be either glass-epoxy or paper-phenol. The structure of the glass-epoxy laminate surface is characterized by spatial nonuniformity caused by the regular structure formed by regions of glass fibers and resin in the top layer of the laminate. The higher value of thermal expansion of the resin than of the glass fiber means that the area of the resin expands more than that of the glass fiber. This causes local compressive stress in the solder layer and as a result promotes whisker growth in the area of the alloy soldered on the Cu layer over the glass fiber. This effect does not occur on the surface of an alloy soldered on Cu layer over a paper-phenol laminate.  相似文献   
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