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71.
Chalissery Jaime M. Gries Regine Alamsetti Santosh K. Ardiel Madison J. Gries Gerhard 《Journal of chemical ecology》2022,48(3):302-311
Journal of Chemical Ecology - Four species of Tetramorium pavement ants are known to guide foraging activities of nestmates via trail pheromones secreted from the poison gland of worker ants, but... 相似文献
72.
Effect of mixer geometry and operating conditions on flow mixing of shear thinning fluids with yield stress
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Jaime Sossa‐Echeverria Fariborz Taghipour 《American Institute of Chemical Engineers》2014,60(3):1156-1167
Flow mixing of a non‐Newtonian fluid in a stirred tank equipped with a side‐entry impeller was observed using particle image velocimetry (PIV). The effects of some geometrical parameters including the mixer shape and impeller type and position on the flow pattern were studied on velocity fields obtained at different locations inside the mixing domain. The different flow structures revealed that the ratio of inertial and viscous forces largely defines the flow pattern. Dead zones were observed inside the tank due to the rheological properties of the fluid. The size of the dynamic regions and the average velocity near the impeller were enhanced by increasing the suction area. Likewise, large pitch ratios were found to improve the active mixing zone and the axial discharge. Curves for the power and pumping numbers are reported for different axial flow impellers. © 2013 American Institute of Chemical Engineers AIChE J, 60: 1156–1167, 2014 相似文献
73.
Jose R. Infante Luis A. Villarreal Arturo Cisneros Ren D. Peralta Raúl G. Lpez María E. Trevio Jaime Wisniak 《应用聚合物科学杂志》1996,62(13):2311-2316
The assembly of a stirred tank reactor capable of precise reaction temperature control is described. The unit allows easy on-line determination of the thermal effect and calculation of heat transfer coefficients and heat capacities. Construction elements are standard, low cost, and high quality. Temperature control is achieved by a heating-cooling loop integrated to the reactor jacket and a cascade control procedure. An important feature of the equipment is the integration of the data acquisition system with the supervisory control system that allows the capability of an advanced strategy for process control and data acquisition. The capability of the reaction system is demonstrated for the microemulsion polymerization of vinyl acetate, by the use of batch and isothermal operational modes. The course of the reaction is followed on-line by the temperature variation of the jacket. Procedures are described for the calibration of the unit. The reactor developed is versatile, is easy to configure and extend, is low cost, and can compete advantageously with commercial reactor units such as the Mettler RC1. © 1996 John Wiley & Sons, Inc. 相似文献
74.
Dr. Pablo Valverde J. Daniel Martínez Prof. F. Javier Cañada Dr. Ana Ardá Prof. Jesús Jiménez-Barbero 《Chembiochem : a European journal of chemical biology》2020,21(21):2999-3025
Carbohydrates play a pivotal role in intercellular communication processes. In particular, glycan antigens are key for sustaining homeostasis, helping leukocytes to distinguish damaged tissues and invading pathogens from healthy tissues. From a structural perspective, this cross-talk is fairly complex, and multiple membrane proteins guide these recognition processes, including lectins and Toll-like receptors. Since the beginning of this century, lectins have become potential targets for therapeutics for controlling and/or avoiding the progression of pathologies derived from an incorrect immune outcome, including infectious processes, cancer, or autoimmune diseases. Therefore, a detailed knowledge of these receptors is mandatory for the development of specific treatments. In this review, we summarize the current knowledge about four key C-type lectins whose importance has been steadily growing in recent years, focusing in particular on how glycan recognition takes place at the molecular level, but also looking at recent progresses in the quest for therapeutics. 相似文献
75.
Karola B?hme Inmaculada C. Fern��ndez-No Jose M. Gallardo Benito Ca?as Pilar Calo-Mata 《Food and Bioprocess Technology》2011,4(6):907-918
Foodborne intoxications caused by the consumption of fish and other products of marine origin contaminated with bacterial
pathogens are an ever-present threat, either due to bacteria and/or its metabolites. In addition, the rapid spoilage of seafood
due to microbial activity, results in high economic losses. The development of the microbiota in seafood products depends
on the microbiological ambience of capture, processing and storage, and the applied preservation method. Thus, pathogenic
and spoilage bacterial species in seafood may come from the indigenous microbiota of the aquatic ambience or are introduced
by contamination during processing. Rapid and accurate bacterial species identification is essential for an effective control
program to ensure safety and quality of either processed or minimally processed seafood. In the present work, matrix-assisted
laser desorption ionization-time of flight mass spectrometry was successfully applied to identify 26 bacterial strains isolated
from fresh fish and processed seafood samples. The approach was based on the comparison of unknown spectra to a reference
spectral library and demonstrated to be a fast and accurate technique for bacterial species differentiation, which can be
used for the rapid identification of foodborne pathogens and spoilage bacteria potentially present in products of marine origin. 相似文献
76.
Morcilla de Burgos is the most famous blood sausage in Spain. However, while producers are interested in extending its shelf life, the consumer is increasingly demanding more natural food. This situation has led to the current search for new and mild preservation technologies. Two batches of four different products: control without any treatment, control with organic acid salts (CnOAS; a 3% mixture of potassium/sodium l-lactate), control with high hydrostatic pressure processing (CnHPP; 600MPa-10min), and a combination of both treatments (OAS+HPP), were carried out to evaluate any synergistic effect that occurs when combining OAS and HPP, and the influence of different preservative treatments on the spoilage bacterial population and their evolution. HPP (with or without addition of OAS) can be considered the most suitable method for preserving morcilla de Burgos as it does not produce negative changes in sensory attributes. No clear selective effect of different treatments on the composition of the spoilage bacteria was seen and similar spoilage patterns were observed independently of the preservation treatment used. 相似文献
77.
Alexander Apelblat Taisa Zaharoskin Jaime Wisniak Emmanuel Korngold 《Journal of the American Oil Chemists' Society》1996,73(2):239-244
Formamide,N-methylformamide,N-dimethylformamide, dimethylsulfoxide, 1,2-butanediol, and 2-butane-1,4-diol were considered as potential extractants of fatty
acids from soybean and jojoba oils. Ternary liquid-liquid phase diagrams at 298.15 K, distribution, and selectivity coefficients
of oleic acid are reported. Of the investigated solvents, onlyN-methylformamide and 1,2-butanediol have desirable extraction characteristics. 相似文献
78.
79.
The spray atomization and combustion characteristics of canola methyl ester (CME) biofuel are compared to those of petroleum based No. 2 diesel fuel in this paper. The spray flame was contained in an optically accessible combustor which was operated at atmospheric pressure with a co-flow of heated air. Fuel was delivered through a swirl-type air-blast atomizer with an injector orifice diameter of 300 μm. A two-component phase Doppler particle analyzer was used to measure the spray droplet size, axial velocity, and radial velocity distributions. Radial and axial distributions of NO, CO, CO2 and O2 concentrations were also obtained. Axial and radial distributions of flame temperature were recorded with a Pt–Pt/13%Rh (type R) thermocouple. The volumetric flow rates of fuel, atomization air and co-flow air were kept constant for both fuels. The droplet Sauter mean diameter (SMD) at the nozzle exit for CME biofuel spray was smaller than that of the No. 2 diesel fuel spray, implying faster vaporization rates for the former. The flame temperature decreased more rapidly for the CME biofuel spray flame than for the No. 2 diesel fuel spray flame in both axial and radial directions. CME biofuel spray flames produced lower in-flame NO and CO peak concentrations than No. 2 diesel fuel spray flames. 相似文献
80.
Christina Jane Vellan Jaime Jacqueline Jayapalan Boon-Koon Yoong Azlina Abdul-Aziz Sarni Mat-Junit Perumal Subramanian 《International journal of molecular sciences》2022,23(4)
Pancreatic ductal adenocarcinoma (PDAC), a highly aggressive malignancy with a poor prognosis is usually detected at the advanced stage of the disease. The only US Food and Drug Administration-approved biomarker that is available for PDAC, CA 19-9, is most useful in monitoring treatment response among PDAC patients rather than for early detection. Moreover, when CA 19-9 is solely used for diagnostic purposes, it has only a recorded sensitivity of 79% and specificity of 82% in symptomatic individuals. Therefore, there is an urgent need to identify reliable biomarkers for diagnosis (specifically for the early diagnosis), ascertain prognosis as well as to monitor treatment response and tumour recurrence of PDAC. In recent years, proteomic technologies are growing exponentially at an accelerated rate for a wide range of applications in cancer research. In this review, we discussed the current status of biomarker research for PDAC using various proteomic technologies. This review will explore the potential perspective for understanding and identifying the unique alterations in protein expressions that could prove beneficial in discovering new robust biomarkers to detect PDAC at an early stage, ascertain prognosis of patients with the disease in addition to monitoring treatment response and tumour recurrence of patients. 相似文献