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71.
Bartomiej Samociuk Daniel Medyski Daniel Nowak Joanna Kawa-Rygielska Kacper
wiechowski Alan Gasiski Andrzej Janus 《Materials》2022,15(9)
The aim of this study was to attempt to use barley malt as a natural, organic binder in the technology of molding sand. TGA analysis of the binder was performed, during which temperatures of thermal decomposition of its components were determined. The results of TG/DTG analysis show that a loss of ~75% of mass of the MB binder is organic matter. Over 50% of this is starch. The results indicate the possibility of using a binder made of barley malt as a binding material for quartz sand grains. This fact was confirmed by tests carried out with use of SEM. During the observations, it was found that barley malt forms smooth bridges connecting individual grains of quartz sand. The typical properties of molding sands with barley malt were also determined, compared to sands containing commonly used binders. At the same time, the influence of the content of this binder on flowability, permeability, strength properties, and wear resistance was assessed. It has been found that increasing the binder content in molding mass results in an increase in strength and wear resistance, as opposed to flowability and permeability. Test castings were also made. It was found that the addition of a binder made of barley malt has a positive effect on the surface quality of castings. This was confirmed by roughness measurements of the test castings. At the same time, a tendency to excessive gas evolution during pouring was shown, with higher contents of this binder. Moreover, greater amounts of barley malt in the molding sand (MB 5%) as compared to the lower content (MB 2%) increased the thickness of the burnt layer of the sand by 25%. This is due to the exothermic reaction when more binder is burnt. It is extremely important from the point of view of the regeneration of molding sand. 相似文献
72.
Marcel Best Andrew N. Gifford Sung Won Kim Ben Babst Markus Piel Frank Rösch Joanna S. Fowler 《Journal of labelled compounds & radiopharmaceuticals》2012,55(1):39-43
A recent report that the aliphatic dicarboxylic acid, azelaic acid (1,9‐nonanedioic acid) but not related acids, suberic acid (1,8‐octanedioic acid) or sebacic (1,10‐decanedioic acid) acid induces systemic acquired resistance to invading pathogens in plants stimulated the development of a rapid method for labeling these dicarboxylic acids with 11C and 14C for in vivo mechanistic studies in whole plants. 11C‐labeling was performed by reaction of ammonium [11C]cyanide with the corresponding bromonitrile precursor followed by hydrolysis with aqueous sodium hydroxide solution. Total synthesis time was 60 min. Median decay‐corrected radiochemical yield for [11C]azelaic acid was 40% relative to trapped [11C]cyanide, and specific activity was 15 GBq/µmol. Yields for [11C]suberic and sebacic acids were similar. The 14C‐labeled version of azelaic acid was prepared from potassium [14C]cyanide in 45% overall radiochemical yield. Radiolabeling procedures were verified using 13C‐labeling coupled with 13C‐NMR and liquid chromatography–mass spectrometry analysis. The 11C and 14C‐labeled azelaic acid and related dicarboxylic acids are expected to be of value in understanding the mode‐of‐action, transport, and fate of this putative signaling molecule in plants. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
73.
The middle course of the Neman River is the habitat of 120 water beetle species. Water beetles were most abundant in the Neman River, its major tributaries and oxbow lakes. They consisted of four synecological groups: rheobiontic and rheophilic organisms, type ??a?? and ??b?? stagnobionts. The diverse types of aquatic environments constitute faunal centers which, in addition to the specific and dominant Coleopteran populations, also feature migrational elements. The presence of close relations between the fauna of different environments indicates that they form a single, faunistically integrated hydrological system. 相似文献
74.
Marcin Markowski Adam Kaliński Joanna Skwarska Jarosław Wawrzyniak Mirosława Bańbura Janusz Markowski Piotr Zieliński Jerzy Bańbura 《Bulletin of environmental contamination and toxicology》2013,91(3):302-305
The aim of this study was to determine the possibility of using feathers of blue tit nestlings to assess the level of endogenous accumulation of lead. For this purpose we conducted an experiment with lead application to randomly chosen nestlings from eight randomly drawn broods. Five days after the exposure, feathers of lead-treated nestlings had significantly higher lead concentrations than control nestlings. This result suggests that feathers can be used as reliable non-destructive bioindicators to assess the level of heavy metals originating from contaminated food, which is of great significance for comparative studies on ecological consequences of pollution. 相似文献
75.
Maria del C. Valdés Hernández PhD Rory J. Piper BMedSc Xin Wang MSc Ian J. Deary PhD Joanna M. Wardlaw MD 《Journal of magnetic resonance imaging : JMRI》2013,38(4):774-785
Enlarged perivascular spaces (EPVS), visible in brain MRI, are an important marker of small vessel disease and neuroinflammation. We systematically evaluated the literature up to June 2012 on possible methods for their computational assessment and analyzed confounds with lacunes and small white matter hyperintensities. We found six studies that assessed/identified EPVS computationally by seven different methods, and four studies that described techniques to automatically segment similar structures and are potentially suitable for EPVS segmentation. T2‐weighted MRI was the only sequence that identified all EPVS, but FLAIR and T1‐weighted images were useful in their differentiation. Inconsistency within the literature regarding their diameter and terminology, and overlap in shape, intensity, location, and size with lacunes, conspires against their differentiation and the accuracy and reproducibility of any computational segmentation technique. The most promising approach will need to combine various MR sequences and consider all these features for accurate EPVS determination. J. Magn. Reson. Imaging 2013;38:774–785. © 2013 Wiley Periodicals, Inc. 相似文献
76.
77.
Joanna M.L. Geddes Alan Tennant M. Anne Chamberlain 《Disability and rehabilitation》2013,35(12):529-538
Purpose : This paper describes the application of the handicap dimension of the International Classification of Impairments, Disabilities and Handicaps. Method : A method of assessing four of the six roles (or areas of expected competency) was developed and applied to an inpatient population, aged 16 to 65 years, receiving specialist rehabilitation following neurological damage. Handicap assessment was a collaborative process by a multidisciplinary team. Difficulties were experienced in measuring inter-rate reliability in the busy, clinical setting. Results : We conclude that handicap assessment in an in-patient rehabilitation unit which uses a multidisciplinary approach to treating patients with complex physical, sensory and cognitive problems is both feasible and useful. Conclusion : The developed scale, The Leeds Assessment Scale of Handicap, provides a valid and valuable summary of human disadvantage, complementing the common disability assessments. 相似文献
78.
Enhanced Retroviral Transduction of 5-Fluorouracil-Resistant Human Bone Marrow (Stem) Cells Using a Genetically Modified Packaging Cell Line 下载免费PDF全文
Povey Joanna; Weeratunge Nishanthi; Marden Chloe; Sehgal Amita; Thrasher Adrian; Casimir Colin 《Blood》1998,92(11):4080-4089
Pluripotent hematopoietic stem cells (PHSC) are rare cells capableof multilineage differentiation, long-term reconstituting activity andextensive self-renewal. Such cells are the logical targets for manyforms of corrective gene therapy, but are poor targets for retroviralmediated gene transfer owing to their quiescence, as retroviraltransduction requires that the target cells be cycling. To try andsurmount this problem we have constructed a retroviral producer linethat expresses the membrane-bound form of human stem cell factor (SCF)on its cell surface. These cells are capable, therefore, of deliveringa growth signal concomitant with recombinant retroviral vectorparticles. In this report we describe the use of this cell line totransduce a highly quiescent population of cells isolated from adulthuman bone marrow using the 5-fluorouracil (FU) resistance technique ofBerardi et al. Quiescent cells selected using this technique weretransduced by cocultivation with retroviral producers expressingsurface bound SCF or with the parent cell line that does not. Followingcoculture, the cells were plated in long-term bone marrow culture for afurther 5 weeks, before plating the nonadherent cells in semisolidmedia. Colonies forming in the semisolid media over the next 14 dayswere analyzed by polymerase chain reaction for the presence of theretroviral vector genome. Over six experiments, the transductionfrequency of the quiescent 5-FU resistant cells using theSCF-expressing producer line averaged about 20%, whereas thosetransduced using the parent producer line showed evidence of reducedlevels or no transduction. 相似文献
79.
中国和希腊,看似遥远的两个国家在古代哲学思想方面却近乎一致。古人一直在探寻自然现象的本质问题,并一直在试图回答这些系统联系的基础。在诸多问题中,他们最感兴趣的是天体运动,健康与疾病的相互关系,以及物质运动的原理。通过探究两种不同文化背景基础哲学理论的异同。 相似文献
80.
Noble SM Coast J Brookes S Neal DE Abrams P Peters TJ Donovan JL 《The Journal of urology》2002,168(6):2476-2482
PURPOSE: We evaluated the cost-effectiveness of noncontact laser therapy compared with transurethral prostate resection and conservative treatment in men with symptoms associated with benign prostatic enlargement. MATERIALS AND METHODS: A total of 340 men with uncomplicated lower urinary tract symptoms participated in a large multicenter pragmatic randomized trial called the CLasP (Conservative management, Laser therapy, transurethral resection of the Prostate) study. Costs to the United Kingdom National Health Service and patients were determined from the time of randomization to the 7.5-month followup. Incremental cost-effectiveness ratios using conservative management as the base case were calculated for certain trial outcomes, including International Prostate Symptom Score (I-PSS), I-PSS quality of life score, maximum urinary flow, post-void residual urine volume, quality adjusted life-years and a composite measure of success based on I-PSS and maximum urinary flow. One-way sensitivity analysis of the basic costs and incremental cost-effectiveness ratios were done from the NHS viewpoint. RESULTS: Mean costs per patient were greatest for noncontact laser therapy and least for conservative management. The incremental cost-effectiveness ratios showed that transurethral prostate resection was more cost-effective than noncontact laser treatment for all primary trial outcomes. The incremental cost-effectiveness ratios of transurethral prostate resection compared with conservative management were pound 81 per unit decrease in the I-PSS score and pound 1,338 per additional successful case per 100 patients. Sensitivity analysis showed that the initial results were robust. CONCLUSIONS: Noncontact laser was the mostly costly treatment option. Transurethral prostate resection was more cost-effective than noncontact laser therapy in terms of symptomatic improvement. In men wishing to delay treatment conservative treatment appears to provide a cost-effective alternative in the short term. 相似文献