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81.
Brucella melitensis, Cronobacter sakazakii and Listeria monocytogenes are important foodborne pathogens in milk and milk products, which are responsible for a variety of diseases that pose serious hazards to public health and food safety. The objective of this study was to develop a novel multiplex RTi‐PCR for the detection of B. melitensis, C. sakazakii and L. monocytogenes and to characterise the potential risk of these pathogens in raw milk and cheese. The raw milk (n = 25) and cheese samples (n = 20) were analysed by multiplex RTi‐PCR assay and detected for quantification of the three pathogens. In this study, B. melitensis, C. sakazakii and L. monocytogenes were simultaneously identified using BMEII0466, mms operon and hly as target genes, respectively. The multiplex RTi‐PCR assay that was developed showed good sensitivity and selectivity for the pathogenic microorganisms (r2 = 0.986–0.997). Multiplex RTi‐PCR results showed that most of the samples were contaminated with the pathogens screened.  相似文献   
82.
Soluble epoxide hydrolase (sEH) is implicated as a potential therapeutic target for inflammation-related pathologies in the context of cardiovascular, central nervous system and metabolic diseases. In our search for novel sEH inhibitors, we designed and synthesized novel analogs of the piperazine urea derivative 4 , a previously discovered dual microsomal prostaglandin E2 synthase-1 (mPGES-1)/soluble epoxide hydrolase (sEH) inhibitor, to evaluate their potential as sEH inhibitors. We identified two 1,3,4-oxadiazol-5-one and -thione congeners (compounds 19 and 20 ), which demonstrated selective sEH inhibition with IC50 values in the two-digit nanomolar range (42 and 56 nM, respectively). These results suggest that the installation of terminal 1,3,4-oxadiazol-5-one/thione functions to the benzyl end can be regarded as a promising secondary pharmacophore in addition to the urea group for sEH inhibition, and compound 19 can be regarded as novel lead structure for further optimization of improved sEH inhibitors.  相似文献   
83.
In this study microbial production of rennin from a commercial strain of Mucor miehei (NRRL 3420) has been accomplished in a continuously fed fermenter. The effects of feed D ‐glucose concentration (2.5–30 g dm−3) on milk clotting activity and on other system variables were investigated at optimum mixing and dilution rates of 400 rpm and 0.0052 h−1, respectively, without pH control. Maximum milk clotting activity (1.24 IU cm−3) occurred when the feed D ‐glucose concentration was 7.5 g dm−3. Enzyme production continued for 500 h, producing a total milk clotting activity of 10 230 IU. At the maximum milk clotting activity point, total protein concentration, milk clotting and proteolytic activities were analysed and compared with those of a commercial rennet. The ratio of milk clotting activity to proteolytic activity, and specific milk clotting activity were determined as 1.55 × 10−3 IU PU−1 and 5.28 IU mg−1 medium protein, respectively, denoting similar characteristics to a commercial rennet after concentration of the fermentation medium. © 1999 Society of Chemical Industry  相似文献   
84.
Dielectric properties of Jordanian oil shales   总被引:1,自引:0,他引:1  
Microwave heating has been suggested by various authors as a suitable technology for extraction of organic material from oil shales. However, one of the limiting factors in the development of this technology is a lack of accurate dielectric property data for design purposes. In this study the dielectric behaviour of El-lajun oil shale is quantified. The dielectric constant and loss factor of El-lajun oil shale were measured at 2470 and 912 MHz using the cavity perturbation technique. The effects of organic content, temperature, and moisture content on the microwave heating efficiency were quantified. Coaxial probe technique was also employed to study the effect of frequency on dielectric properties of oil shale. Generally, it was found that all samples were of low dielectric loss at room temperature with the imaginary part of permittivity falling significantly after the moisture was removed. This suggests that the major contribution in the dielectric loss is due to the presence of free and/or interlayer water. It was found that both the real and imaginary part of complex permittivity increased with a rise in temperature from 20 up to 80 °C, then dropped significantly at about 100 °C before staying approximately constant up to a temperature of about 480 °C. From this temperature both the real and imaginary parts of complex permittivity increased sharply with further increase in temperature. An attempt was also made to correlate the dielectric properties of the bulk shale sample with the organic content. However, no correlation between dielectric properties and organic matter content was found.  相似文献   
85.
AFMC-AIMECS meetings are internationally organized biannually by the Asian Federation for Medicinal Chemistry (AFMC) and are focused on recent studies in drug discovery and development both in academia and industry. Member organizations of the AFMC are the Pharmaceutical Society of Japan, the Chinese Pharmaceutical Association, the Royal Australian Chemical Institute, the Pharmaceutical Society of Korea, the Korean Chemical Society, the Chemical Society Located in Taipei, the Indonesian Society of Medicinal Chemistry, the Medicinal Chemistry Section of the Israel Chemical Society, and the Computer-Aided Drug Design & Development Society in Turkey. Each time, the symposium is organized within these member countries. The AIMECS 2019 symposium was held in Turkey this year, as Prof. Dr. Esin Aki-Yalcin is the current president of the AFMC (2018–2020); the next AIMECS meeting will be organized in 2021 in Tokyo, Japan. In this report, we discuss key topics at the 12th AFMC International Medicinal Chemistry Symposium — New Avenues for Design and Development of Translational Medicine (AIMECS 2019) held in Istanbul, September 8–11, 2019.  相似文献   
86.
Treatability of paint manufacturing wastewater (PMW) by electrocoagulation (EC) process was investigated. Effects of operating parameters for the EC process such as electrode type (Al or Fe), initial pH (2–10), current density (5–80 A/m2) and operating time (0–50 min) were evaluated for optimum operating conditions. The highest removal efficiencies for COD and TOC in PMW were obtained with 93% and 88% for Fe and 94% and 89% for Al electrodes at the optimum conditions (35 A/m2, 15 min and pH 6.95). Operating costs for removal of PMW at the optimum conditions were calculated for Fe and Al electrodes as 0.187 €/m3 and 0.129 €/m3. Toxicity test was carried out to obtain information about toxic effect of the raw and treated wastewaters at optimum operating conditions. The samples measured by respirometric method contained hardly toxicities. Performance of Al electrode was better than that of Fe electrode in terms of removal efficiency and operating cost.  相似文献   
87.
The nutritional quality of the protein in the leaves of 11 Asphodeline (Liliaceae) species was investigated by the determination of the amino acid composition and calculation of several nutritional parameters. The average protein content was 4.7% and ranged from 2.5% in Asphodeline damascena ssp. rugosa to 8.2% in A. turcica. The most abundant essential amino acids were Thr (5.7%), Val (6.0%), Ile (4.7%), and Trp (2.1%). The amino acid composition of Asphodeline peshmeniana was well equilibrated according to Food and Agriculture Organisation standards, but Lys and sulphur amino acids were at limiting concentrations in all the other taxa. Determination of the protein efficiency ratio and biological value revealed that the protein in the leaves of Asphodeline species is of high nutritional quality. Hence, the Asphodeline leaves that are typically used in Turkey for the preparation of salads, represent a good source of protein with high levels of several essential amino acids and a good nutritional value. Analysis of the similarity based on the amino acid composition indicated the existence of different clusters that are consistent with the taxonomical classification, area of distribution, and morphological similarities of the Asphodeline species.  相似文献   
88.
The effects of extracted natural antioxidant (laurel and myrtle) on the sensory, chemical (TVB‐N, TBARS, PV, FFA and pH) and microbiological (total viable count, psychrotrophic bacteria and Enterbacteriaceae counts) properties of vacuum‐packaged European eel (Anguilla anguilla) stored at 4 ± 1 °C were investigated. The TBARS values of myrtle were significantly lower than that of other groups. The peroxide value was low for European eel treated with myrtle and laurel extract. The FFA‐free fatty acid concentration increased from 0.44 (% oleic acid) (2.03) in the eel during 24 days of storage. The values of pH showed statistically significant (P < 0.05) changes for all groups. The myrtle significantly reduced bacterial growth in fillets (P < 0.05). The microbiological limit of 7 log cfu per gram did not exceed in the treated groups. Data showed that the extracts of myrtle and laurel contain substances that inhibit oxidation of lipids and growth of bacteria in European eel, indicating the potential value of these extracts to extend the shelf life of fish.  相似文献   
89.
The superconducting Bi1.6Pb0.4Sr2Ca2Cu3?x W x O10+y (x=0.00, 0.05, 0.10, 0.15) bulk samples were prepared by the solid-state reaction method. The effects of W substitution on the BSCCO system have been investigated by the electrical resistivity (ρ-T), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), magnetic hysteresis and critical current density measurements. It has been found that the Bi-(2212) low-T C phase is formed for all the substitution levels, together with the Bi-(2223) high-T C phase. The results obtained from the XRD data show that the Bi-(2223) phase gradually transforms into the Bi-(2212) phase with increasing W substituting for Cu. In addition, from the magnetization measurements at the temperatures below the zero resistance temperatures of the samples, we have observed that a decreasing in magnitude of |M| with the increasing measurement temperature and W concentration. Therefore, the decreasing of |M| related to superconducting volume seems to imply an existence of flux-pinning centers in our samples.  相似文献   
90.
The investigation of dynamic response for civil engineering structures largely depends on a detailed understanding of their dynamic characteristics, such as the natural frequencies, mode shapes, and modal damping ratios. Dynamic characteristics of structures may be obtained numerically and experimentally. The finite-element method is widely used to model structural systems numerically. However, there are some uncertainties in numerical models. Material properties and boundary conditions may not be modeled correctly. There may be some microcracks in the structures, and these cracks may directly affect the modeling parameters. Modal testing gives correct uncertain modeling parameters that lead to better predictions of the dynamic behavior of a target structure. Therefore, dynamic behavior of special structures, such as minarets, should be determined with ambient vibration tests. The vibration test results may be used to update numerical models and to detect microcracks distributed along the structure. The operational modal analysis procedure consists of several phases. First, vibration tests are carried out, spectral functions are produced from raw measured acceleration records, dynamic characteristics are determined by analyzing processed spectral functions, and finally analytical models are calibrated or updated depending on experimental analysis results. In this study, an ambient vibration test is conducted on the minaret under natural excitations, such as wind effects and human movement. The dynamic response of the minaret is measured through an array of four trixial force-balanced accelerometers deployed along the whole length of the minaret. The raw measured data obtained from ambient vibration testing are analyzed with the SignalCAD program, which was developed in MATLAB. The employed system identification procedures are based on output-only measurements because the forcing functions are not available during ambient vibration tests. The ModalCAD program developed in MATLAB is used for dynamic characteristic identification. A three-dimensional model of the minaret is constructed, and its modal analysis is performed to obtain analytical frequencies and mode shapes by using the ANSYS finite-element program. The obtained system identification results have very good agreement, thus providing a reliable set of identified modal properties (natural frequencies, damping ratios, and mode shapes) of the structure, which can be used to calibrate finite-element models and as a baseline in health monitoring studies.  相似文献   
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