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351.
Erdemir ET Batta R Spielman S Rogerson PA Blatt A Flanigan M 《Accident; analysis and prevention》2008,40(3):1105-1114
In a recent paper, Tokar Erdemir et al. (2008) introduce models for service systems with service requests originating from both nodes and paths. We demonstrate how to apply and extend their approach to an aeromedical base location application, with specific focus on the state of New Mexico (NM). The current aeromedical base locations of NM are selected without considering motor vehicle crash paths. Crash paths are the roads on which crashes occur, where each road segment has a weight signifying relative crash occurrence. We analyze the loss in accident coverage and location error for current aeromedical base locations. We also provide insights on the relevance of considering crash paths when selecting aeromedical base locations. Additionally, we look briefly at some of the tradeoff issues in locating additional trauma centers vs. additional aeromedical bases in the current aeromedical system of NM. Not surprisingly, tradeoff analysis shows that by locating additional aeromedical bases, we always attain the required coverage level with a lower cost than with locating additional trauma centers. 相似文献
352.
Konuk M Korcan E Dülgerbaki S Altindiş M 《International journal of food microbiology》2007,115(3):343-347
Nontuberculous mycobacteria (NTM) have become a significant cause of infection with the emergence of HIV/AIDS, primarily Mycobacterium avium complex members, and NTM transmitted to humans from the environment (water, fruit, vegetables, beef, and milk). The objectives of this study were to show the presence of mycobacteria in milk and to determine their role as possible sources of human infection. For this, raw milk samples (N=35) were decontaminated with sodium dodecyl (lauryl) sulfate (SDS)-NaOH and inoculated on to L?wenstein-Jensen medium. After confirming positive 15 slides, isolated from milk by Ziehl-Neelsen technique, they were identified by PCR-Restriction Fragment Length Polymorphism Analysis (PRA). Nine hospital isolates which were identified as Mycobacterium tuberculosis complex by BACTEC were used at control group. We have detected Mycobacterium terrae, Mycobacterium kansassii, Mycobacterium agri at the end of the identification. Two mycobacterial raw milk isolates were not able to be identified by PRA. PRA patterns' were found to be similar to those which obtained University Faculty of Medical by BACTEC. The results showed that raw milk is to be possible sources for human infection. That is why UHF sterilized milk should be consumed. 相似文献
353.
Flavanoids are known to interact with proteins to form complexes whose properties depend on the structure of both the flavanoids and the protein. In this study, the fluorescent probe binding method (fluorimetry analysis) and isothermal titration calorimetry (ITC) analysis were used to characterize binding interactions of green tea (GT) flavanoids and milk proteins. The hydrophobicity of the surface sites of milk proteins was estimated using the reconstituted milk–green tea and casein–green tea systems. Reconstituted milk–green tea and casein–green tea samples were prepared with different solid-non-fat (SNF) and casein (Cn) concentrations, respectively. It was observed that the number of surface hydrophobic sites decreased in the presence of GT flavanoids for all SNF and Cn concentrations. The decrease in protein surface hydrophobicity was explained by the hydrophobic binding between milk proteins and GT flavanoids. The binding enthalpies obtained from ITC analysis implied that interaction was non-covalent between catechin and β-casein. 相似文献
354.
Emotional reactions to red, green, blue, and gray colors in a living room were investigated using a self-report measure. Participants first watched a short video of a 3D model of a living room. Next, they were asked to match the living rooms with facial expressions of six basic emotions. The most stated emotions associated for the red room were disgust and happiness, while the least stated emotions were sadness, fear, anger, and surprise; for the green room, neutral and happiness were the most stated emotions, and anger, surprise, fear, and sadness were the least stated ones; for the blue room, neutral was the most stated emotion, while the least stated emotions were anger and surprise. Neutral, disgust, and sadness were the most stated emotions for the gray room. Gender differences were not found in human emotional reactions to living rooms with different wall colors. 相似文献
355.
Zeynep Aksoylu Özbek Kıvılcım Yıldız Pelin Günç Ergönül Elif İyilikeden Türkan Uzlaşır 《European Journal of Lipid Science and Technology》2023,125(10):2300024
The tomato processing industry generates a significant amount of a by-product (pomace), which is a mixture of peels and seeds. The purpose of this study was to compare the effects of conventional oven-roasting (at 120°C, 150°C, and 180°C for 25 min) and innovative microwave-roasting (at 240, 388, and 536 W for 3 min) pretreatments on the physicochemical properties, fatty acid profiles, bioactive contents, and aroma profiles of tomato seeds and their hexane-extracted oils. The total flavonoids contents (TFCs) of the seeds decreased from 258.40 to 141.20 mg quercetin equivalent (QE) per kg after roasting. All roasting treatments improved the extractability of both α- and γ-tocopherols. The amounts of total tocopherols in the seeds increased from 917.61 to 1256.25 mg kg–1 after pretreatment. Luteolin was found to be the most abundant phenolic in seed oils, increasing from 10.68 to 91.72 mg kg–1, followed by quercetin, ferulic acid, and catechin. Within each roasting technique, the ones treated at 150°C and 338 W yielded the oils with the highest concentrations of aroma compounds, 418 and 92 mg kg–1, respectively. The detrimental effect of microwave-roasting on these compounds was more pronounced. In conclusion, microwave-roasting at shorter times than conventional roasting produced tomato seed oils with well-preserved bioactive components and few unfavorable changes. Industrial relevance: Conventional oven-roasting has been widely applied to oilseeds to improve oil yield as well as to obtain desirable sensory characteristics of extracted oils for years. However, longer roasting times may also cause detrimental changes in the properties of oils. On the other side, microwave-assisted applications as an emerging technology provide homogenous and well-controlled heat distribution, shorter treatment times, and considerable energy savings for the processing of various foods. Microwave technology has been easily scaled up and is currently employed for sterilization, drying, pasteurization, precooking, and extraction by the food and chemistry industries. Therefore, the present research suggests the use of microwaves for comparatively short roasting times to produce edible oils with enhanced physicochemical attributes and bioactives contents, and well-maintained sensory properties. This promising innovative technology has the potential to be industrialized for a cost-effective seed roasting process. 相似文献
356.
Ebru Birlik Özkütük Sibel Emir Diltemiz Elif Özalp Arzu Ersöz Rıdvan Say 《Journal of Industrial and Engineering Chemistry》2013,19(6):1788-1792
In this study, a novel quartz crystal microbalance (QCM) based on the modification of paraoxon-imprinted polymer onto a QCM with a high selectivity and sensitivity has been developed for the determination of paraoxon. The QCM sensor has characterized using AFM and ellipsometer. The performance of the QCM sensor has evaluated and presented good reproducibility, shorter response time (20 min), wider linear range (0.02–10 μM) and low detection limit (0.02 μM). The results have shown that the selectivity of QCM sensor has found as being very high in the presence of parathion which is similar in structure with paraoxon. 相似文献
357.
Seyda Korkut Ozoner Elif Erhan Faruk Yilmaz Pinar Ergenekon Ismail Anil 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(4):727-732
BACKGROUD: This study describes the construction of an electrochemical formaldehyde biosensor based on poly(glycidyl methacrylate‐co‐3‐methylthienyl methacrylate)/formaldehyde dehydrogenase/polypyrrole [poly(GMA‐co‐MTM)/FDH/PPy] composite film electrode. Formaldehyde dehydrogenase (FDH) was chemically immobilized via the epoxy groups of the glycidyl methacrylate (GMA) side chain of the polymer. Formaldehyde measurements were conducted in 0.1 mol L?1, pH 8 phosphate buffer solution (PBS) including 0.1 mol L?1 KCl, 0.5 mmol L?1 of NAD+ (cofactor of the enzyme) and 1 mmol L?1 of 1,2‐napthoquinone‐4‐sulfonic acid sodium salt (NQS) as mediator with an applied potential of ? 0.23 V (vs. Ag/AgCl, 3 mol L?1 NaCl). Analytical parameters of the biosensor were calculated and discussed. The biosensor was tested in rain water samples. RESULTS: Sensitivity was found to be 15 000 per mmol L?1 (500 nA ppm?1) in a linear range between 0.1 ppm and 3 ppm (3.3–100 µmol L?1). A minimum detectable concentration of 4.5 ppb (0.15 µmol L?1) (S/N = 3) with a relative standard deviation (RSD) of 0.73% (n = 5) was obtained from the biosensor. Response time of the biosensor was very short, reaching 99% of its maximum response in about 4 s. The biosensor was also tested for formaldehyde measurements in rain water samples. Formaldehyde concentrations in samples were calculated using the proposed biosensor with recovery values ranged between 92.2 and 97.7% in comparison with the colorimetric Nash method. CONCLUSION: The poly(GMA‐co‐MTM)/FDH/PPy) electrode showed excellent measurement sensitivity in comparison with other formaldehyde biosensor studies. Strong chemical bonding between the enzyme and the copolymer was created via the epoxy groups of the composite film. The proposed biosensor could be used successfully in rain waters without a pretreatment step. © 2012 Society of Chemical Industry 相似文献
358.
Maria Mortoglou Francesc Miralles Elif Damla Arisan Alwyn Dart Stipo Jurcevic Sigrun Lange Pinar Uysal-Onganer 《International journal of molecular sciences》2022,23(3)
Pancreatic ductal adenocarcinoma (PDAC) is the most common and aggressive type of pancreatic cancer (PCa) with a low survival rate. microRNAs (miRs) are endogenous, non-coding RNAs that moderate numerous biological processes. miRs have been associated with the chemoresistance and metastasis of PDAC and the presence of a subpopulation of highly plastic “stem”-like cells within the tumor, known as cancer stem cells (CSCs). In this study, we investigated the role of miR-21, which is highly expressed in Panc-1 and MiaPaCa-2 PDAC cells in association with CSCs. Following miR-21 knockouts (KO) from both MiaPaCa-2 and Panc-1 cell lines, reversed expressions of epithelial–mesenchymal transition (EMT) and CSCs markers were observed. The expression patterns of key CSC markers, including CD44, CD133, CX-C chemokine receptor type 4 (CXCR4), and aldehyde dehydrogenase-1 (ALDH1), were changed depending on miR-21 status. miR-21 (KO) suppressed cellular invasion of Panc-1 and MiaPaCa-2 cells, as well as the cellular proliferation of MiaPaCa-2 cells. Our data suggest that miR-21 is involved in the stemness of PDAC cells, may play roles in mesenchymal transition, and that miR-21 poses as a novel, functional biomarker for PDAC aggressiveness. 相似文献
359.
AyhanS. Demir
zge eenoglu Elif Eren Birsu Hosrik Martina Pohl Elena Janzen Doris Kolter Ralf Feldmann Pascal Dünkelmann Michael Müller 《Advanced Synthesis \u0026amp; Catalysis》2002,344(1):96-103
(R)‐Benzoins and (R)‐2‐hydroxypropiophenone derivatives are formed on a preparative scale by benzaldehyde lyase (BAL)‐catalyzed C−C bond formation from aromatic aldehydes and acetaldehyde in aqueous buffer/DMSO solution with remarkable ease in high chemical yield and high optical purity. The substrate range of this thiamin diphosphate‐dependent enzyme was examined with respect to a broad applicability of this benzoin condensation‐type reaction in stereoselective synthesis. 相似文献