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391.
In this paper,negative selection and genetic algorithms are combined and an improved bi-objective optimization scheme is presented to achieve optimized negative...  相似文献   
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393.
Available reports have confirmed a link between bacterial infection and the progression of different types of cancers, including colon, lungs, and prostate cancer. Here we report the Chlamydia pneumonia proteins targeting in endoplasmic reticulum (ER) using in-silico approaches and their possible role in lung cancer etiology. We predicted 48 proteins that target human ER, which may be associated with protein folding and protein-protein interactions during infection. The results showed C. pneumoniae proteins targeting human ER and their implications in lung cancer growth. These targeted proteins may be involved in competitive interactions between host and bacterial proteins, which may change the usual pathway functions and trigger the development of lung cancer. Moreover, C. pneumoniae unfolded protein accumulation in the human ER possibly induces ER stress, consequently activating the unfolded protein response (UPR), and providing a favorable microenvironment for cancer growth. The current study showed the C. pneumoniae protein targeting in ER of host cell and their implication in lung cancer growth. These results may help researchers better manage lung cancer and establish a molecular mechanism for C. pneumoniae lung cancer association.  相似文献   
394.
Ochratoxin A (OTA), one of the most dangerous mycotoxins for human health, has been subjected to numerous studies for separation and detection in minimal amounts. Aptamers as novel recognition elements have been employed to fabricate ultrasensitive biosensors for the detection of OTA and designing delicate analytical tools. This review attempted to comprehensively examine all reported aptamer-based detection and separation platforms for ochratoxin. The most relevant databases were considered to discover all specific aptamers for dealing with OTA. Aptamer-based detection and separation devices specified for OTA were searched for, analyzed, discussed, and classified based on their specifications. The optical aptasensors have gathered a higher interest than electrochemical aptasensors, which can achieve a lower limit of detections. Moreover, some extraction platforms based on these aptamers were also found. However, aptamer-based devices seem to have some challenges in their application.  相似文献   
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Various fluxing materials are added to technical ceramics in an attempt to lower their sintering temperatures and make their processing economical. The effect of 0·3?wt% Li2CO3 addition on the phase, microstructure, phase transition temperatures and dielectric properties of BaTiO3 was investigated in the present study. The addition of 0·3?wt% Li2CO3 was observed to lower the optimum sintering temperature by ??200°C with no second phase formation and cause a five-fold reduction in grain size. Rhombohedral-to-orthorhombic and tetragonal-to-cubic phase transitions at the expected temperatures were evident from the Raman spectra, but the orthorhombic-to-tetragonal phase transition was not clearly discernible. The persistence of various phase(s) at higher temperatures in the flux-added materials indicated that the phase transitions occurred relatively slowly. A decrease in dielectric constant of Li2O-added BaTiO3 in comparison to pure BaTiO3 may be due to the diminished dielectric polarizability of Li?+? in comparison to Ba2?+?.  相似文献   
397.
This research evaluated the effects of Mentha longifolia L. essential oil (EO) in concentrations 0, 50, 150 and 300 ppm and Lactobacillus casei (108–109 CFU/mL) on the growth of Staphylococcus aureus and Listeria monocytogenes during the manufacturing, ripening and storage of Iranian white‐brined cheese. The growth of the two pathogens was significantly reduced (P < 0.01) by both EO concentrations ≥50 ppm and probiotic and their combination in the standard manufacturing and storage process conditions of the cheese. Furthermore, the treatment containing 150 ppm of this EO combined with probiotic had a favourable inhibitory effect on the growth of two pathogenic micro‐organisms and also was the most appropriate treatment in sensory assessment. The synergistic effects of the above‐mentioned concentration level between the essential oil and probiotic were significant compared to other treatments, including essential oil and probiotic only. Thus, a lower concentration of this EO can be used when it is combined with this probiotic.  相似文献   
398.
This paper reviews the process for the commercial production of beryllium-copper master alloy. Emphasis is placed on basics of carbothermic reduction of beryllium oxide in the presence of copper. The product is typically a 4% beryllium copper master alloy which is the feedstock for high performance beryllium copper alloys.  相似文献   
399.
The optimal location of a pickup point on a material handling network is considered. The pickup point is defined as the material exchange point between the material handling system (MHS) and a station. The problem is defined as that of choosing the location of the pickup point to minimize the total cost of material movement in the MHS. A facility location model on directed networks has been developed, and strongly polynomial solution methods are presented.  相似文献   
400.
To extend the predictive capability of existing crack growth models for fibre metal laminates under constant amplitude fatigue loading to variable-amplitude loading, further research on variable-amplitude fatigue mechanisms in fibre metal laminates is necessary. In response to this need, an experimental study into the effects of multiple overloads, underloads and various block-loading sequences on crack growth in the fibre metal laminate Glare was investigated. Crack growth retardation effects were observed in the tests; however, the magnitude of these effects was lower than seen in monolithic aluminium because of fibre bridging. As a result, predictions of the observed behaviour were attempted using an existing constant-amplitude fatigue crack growth model for Glare in combination with a linear damage accumulation law.  相似文献   
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