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1.
Effect of complexation of oxidised corn starch with mineral elements on physicochemical properties 下载免费PDF全文
Sławomir Pietrzyk Teresa Fortuna Lesław Juszczak Dorota Gałkowska Karolina Królikowska Karolina Zięba 《International Journal of Food Science & Technology》2015,50(4):934-941
The objective of this study was to determine the effect of complexation of oxidised starch with mineral elements on its physicochemical properties. Corn starch was oxidised with sodium hypochlorite and, afterwards, modified with ions of potassium, magnesium and iron. Thus, native and modified starches were analysed for: contents of mineral elements, colour parameters (L*a*b*), water binding capacity and solubility in water at temperature of 60 and 80 °C. Thermodynamic characteristics of gelatinisation by DSC, molecular weight distribution by GPC, intrinsic viscosity and pasting properties by RVA were studied. The efficiency of incorporation of metal ions into oxidised corn starch was about 30%, 20% and 20% for potassium, magnesium and iron ions, respectively. The complexation with potassium ions caused the greatest changes in the molecular weight distribution and the intrinsic viscosity of starches and viscosity of starch pastes. Only modification of starch with iron ions affected the colour parameters of the starch. Incorporation of metal ions into starch resulted also in changes in its water binding capacity and solubility in water. 相似文献
2.
Agnieszka M. Wusatowska-Sarnek Martin J. Blackburn Mark Aindow 《Materials Science and Engineering: A》2003,360(1-2):390-395
Methods are described for sample preparation of polycrystalline Ni-based superalloys in order to perform a detailed microstructural characterization. Specific techniques for the precise definition of the various phases present are outlined and these are shown to be useful for the measurement of size, volume fractions and distribution. A number of optical, scanning and transmission microscopy techniques are used to provide the necessary information. 相似文献
3.
Agnieszka J. Klemm Piotr Klemm Kazimierz Rozniakowski Tomasz W. Wojtatowicz 《Building and Environment》2002,37(12):1233-1240
This paper presents the results of the larger study into a potential application of laser radiation for the detection of phase transition processes in low temperatures occurring on the surface layers of cementitious materials. An attempt was made to identify relationships between the environmental conditions—temperature and air humidity, and the selected parameters of the reflected light. Onset of the condensation process and formation of water microdrops on the surface of the material leads to the phase displacement of individual laser rays, which are represented by different speckle images.
Although the analysis of parameters of the reflected light are very difficult in the case of porous materials because of highly developed roughness of the surface structure it has been proved that a dynamic study of the phase transition phenomena can be successfully carried out without mechanical intervention. 相似文献
4.
Agnieszka J Klemm Piotr Klemm Kazimierz Rozniakowski Tomasz W Wojtatowicz 《Building and Environment》2002,37(12):1221-1232
This paper present the results of the investigation into a potential application of laser radiation for the detection of phase transition processes occurring on the surface layers of porous materials. An attempt was made to discuss in the approximation equations, the relationships between coefficients of the reflected light, the temperature and humidity of the surrounding environment. Laser light reflected from the porous surface carries information about the roughness of the structure. The presence of water microdrop on the surface of the porous material, as a result of condensation and thus a phase transition, leads to the phase displacement of individual rays, which is represented by different images. Therefore, a comprehensive analysis of the reflected light parameters allows a dynamic study of the phase transition phenomena without mechanical intervention. 相似文献
5.
Dr inż. J. Kędzia Dr inż. M. Ŀukaniszyn 《Electrical Engineering (Archiv fur Elektrotechnik)》1992,75(5):383-386
Contents The paper provides results of calculations of electric field for parallelepiped and ellipsoidal tanks. The calculations reported in the paper indicate that even at a relatively small volumetric density of charge (q=100 C/m3) the intensity of the electric field in the vapour/air mixture may exceed the critical value (3 MV/m), which may cause a spark discharge. They also show the maximum of the electric field intensity, the maximum potential and energy after the change in shape of the tank, while the volume of the stored liquid remains the same. The calculations of these quantities can be used as a basis for reduction or elimination of the electrostatic ignition hazard.
List of symbols A, B, C factors of the ellipsoidal tank - a, b, H length, width and height of the parallelepiped tank, respectively [m] - E electrical field strength [V/m] - h liquid height in the tank [m] - q volumetric charge density [C/m3] - R radius of the sphere [m] - V electric potential [V] - W E electric field energy [J] - V volume of the tank - r relative dielectric constant - O absolute dielectric constant 8.854×10–12 [As/Vm] 相似文献
Einfluß der Behälterform auf das elektrostatische Feld infolge einer Raumladung
Übersicht Der Beitrag behandelt elektrische Felder in Behältern von der Form eines Parallelepipeds und eines Ellipsoids. Die Berechnungen zeigen, daß selbst bei relativ kleinen Werten der Raumladung (100 C/m3) die elektrische Feldstärke im Dampf-Luftgemisch den kritischen Wert (3 ÖMV/m) überschreiten und einen Durchschlag verursachen kann. Außerdem werden die Maxima der elektrischen Feldstärke, des Potentials und der Energie in Abhängigkeit der Behälterform angegeben unter der Voraussetzung, daß das Volumen der enthaltenen Flüssigkeit konstant bleibt. Die Rechenergebnisse lassen sich als Basis für die Verminderung oder Elimination der Gefahr von Überschlägen verwenden.
List of symbols A, B, C factors of the ellipsoidal tank - a, b, H length, width and height of the parallelepiped tank, respectively [m] - E electrical field strength [V/m] - h liquid height in the tank [m] - q volumetric charge density [C/m3] - R radius of the sphere [m] - V electric potential [V] - W E electric field energy [J] - V volume of the tank - r relative dielectric constant - O absolute dielectric constant 8.854×10–12 [As/Vm] 相似文献
6.
Anita Romanowska Katarzyna Wgrzyn Katarzyna Bury Emilia Sikorska Aleksandra Gnatek Agnieszka Piwkowska Igor Konieczny Adam Lesner Magdalena Wysocka 《International journal of molecular sciences》2021,22(5)
The present study aimed to synthesize novel polycationic polymers composed of N-substituted L-2,3-diaminopropionic acid residues (DAPEGs) and investigate their cell permeability, cytotoxicity, and DNA-binding ability. The most efficient cell membrane-penetrating compounds (O2Oc-Dap(GO2)n-O2Oc-NH2, where n = 4, 6, and 8) showed dsDNA binding with a binding constant in the micromolar range (0.3, 3.4, and 0.19 µM, respectively) and were not cytotoxic to HB2 and MDA-MB-231 cells. Selected compounds used in the transfection of a GFP plasmid showed high transfection efficacy and minimal cytotoxicity. Their interaction with plasmid DNA and the increasing length of the main chain of tested compounds strongly influenced the organization and shape of the flower-like nanostructures formed, which were unique for 5/6-FAM-O2Oc-[Dap(GO2)]8-O2Oc-NH2 and typical for large proteins. 相似文献
7.
8.
Katarzyna Romanowska-Prchnicka Anna Felis-Giemza Marzena Olesiska Piotr Wojdasiewicz Agnieszka Paradowska-Gorycka Dariusz Szukiewicz 《International journal of molecular sciences》2021,22(6)
Tumor necrosis factor-alpha (TNF-α) is a multifunctional Th1 cytokine and one of the most important inflammatory cytokines. In pregnancy, TNF-α influences hormone synthesis, placental architecture, and embryonic development. It was also shown that increased levels of TNF-α are associated with pregnancy loss and preeclampsia. Increased TNF-α levels in complicated pregnancy draw attention to trophoblast biology, especially migratory activity, syncytialisation, and endocrine function. Additionally, elevated TNF-α levels may affect the maternal-fetal relationship by altering the secretory profile of placental immunomodulatory factors, which in turn affects maternal immune cells. There is growing evidence that metabolic/pro-inflammatory cytokines can program early placental functions and growth in the first trimester of pregnancy. Furthermore, early pregnancy placenta has a direct impact on fetal development and maternal immune system diseases that release inflammatory (e.g., TNF-α) and immunomodulatory factors, such as chronic inflammatory rheumatic, gastroenterological, or dermatological diseases, and may result in an abnormal release of cytokines and chemokines in syncytiotrophoblasts. Pregnancy poses a challenge in the treatment of chronic disease in patients who plan to have children. The activity of the disease, the impact of pregnancy on the course of the disease, and the safety of pharmacotherapy, including anti-rheumatic agents, in pregnancy should be considered. 相似文献
9.
Katarzyna Dworaczek Maria Kurzylewska Magdalena Laban Dominika Drzewiecka Agnieszka Pkala-Safiska Anna Turska-Szewczuk 《International journal of molecular sciences》2021,22(8)
In the present work, we performed immunochemical studies of LPS, especially the O-specific polysaccharide (O-PS) of Aeromonas veronii bv. sobria strain K133, which was isolated from the kidney of carp (Cyprinus carpio L.) during an outbreak of motile aeromonad infection/motile aeromonad septicemia (MAI/MAS) on a Polish fish farm. The structural characterization of the O-PS, which was obtained by mild acid degradation of the LPS, was performed with chemical methods, MALDI-TOF mass spectrometry, and 1H and 13C NMR spectroscopy. It was revealed that the O-PS has a unique composition of a linear tetrasaccharide repeating unit and contains a rarely occurring sugar 2,4-diamino-2,4,6-trideoxy-D-glucose (bacillosamine), which may determine the specificity of the serogroup. Western blotting and ELISA confirmed that A. veronii bv. sobria strain K133 belongs to the new serogroup PGO1, which is one of the most commonly represented immunotypes among carp and trout isolates of Aeromonas sp. in Polish aquacultures. Considering the increase in the MAI/MAS incidences and their impact on freshwater species, also with economic importance, and in the absence of an effective immunoprophylaxis, studies of the Aeromonas O-antigens are relevant in the light of epidemiological data and monitoring emergent pathogens representing unknown antigenic variants and serotypes. 相似文献
10.
Dorota Butkiewicz Magorzata Krzeniak Agnieszka Gdowicz-Kosok Monika Giglok Magorzata Marszaek-Zeczak Rafa Suwiski 《International journal of molecular sciences》2021,22(11)
For non-small cell lung cancer (NSCLC), radiotherapy (RT) and platinum-based chemotherapy (CHT) are among the main treatment options. On the other hand, radioresistance and cytotoxic drug resistance are common causes of failure. The epidermal growth factor receptor (EGFR) plays an important role in radioresponse and therapy resistance. We hypothesized that single nucleotide polymorphisms (SNPs) in the EGFR gene might affect individual sensitivity to these treatments, and thus, therapy outcome and prognosis. The association between functional EGFR SNPs and overall (OS), locoregional recurrence-free (LFRS), and metastasis-free (MFS) survival was examined in 436 patients with unresectable NSCLC receiving RT and platinum-based CHTRT. In a multivariate analysis, the rs712830 CC homozygotes showed reduced OS in the whole group (p = 0.039) and in the curative treatment subset (p = 0.047). The rs712829 TT genotype was strongly associated with decreased LRFS (p = 0.006), and the T-C haplotype was a risk factor for locoregional recurrence in our patients (p = 0.003). The rs2227983 GG alone and in combination with rs712829 T was an indicator of unfavorable LRFS (p = 0.028 and 0.002, respectively). Moreover, significant independent effects of these SNPs on OS, LRFS, and MFS were observed. Our results demonstrate that inherited EGFR gene variants may predict clinical outcomes in NSCLC treated with DNA damage-inducing therapy. 相似文献