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101.
Nikoletta Murvai Lajos Kalmar Beata Szabo Eva Schad Andrs Micsonai Jzsef Kardos Lszl Buday Kyou-Hoon Han Peter Tompa Agnes Tantos 《International journal of molecular sciences》2021,22(12)
Disordered plant chaperones play key roles in helping plants survive in harsh conditions, and they are indispensable for seeds to remain viable. Aside from well-known and thoroughly characterized globular chaperone proteins, there are a number of intrinsically disordered proteins (IDPs) that can also serve as highly effective protecting agents in the cells. One of the largest groups of disordered chaperones is the group of dehydrins, proteins that are expressed at high levels under different abiotic stress conditions, such as drought, high temperature, or osmotic stress. Dehydrins are characterized by the presence of different conserved sequence motifs that also serve as the basis for their categorization. Despite their accepted importance, the exact role and relevance of the conserved regions have not yet been formally addressed. Here, we explored the involvement of each conserved segment in the protective function of the intrinsically disordered stress protein (IDSP) A. thaliana’s Early Response to Dehydration (ERD14). We show that segments that are directly involved in partner binding, and others that are not, are equally necessary for proper function and that cellular protection emerges from the balanced interplay of different regions of ERD14. 相似文献
102.
Andrzej Piasecki Beata Wójcik Jacek Łuczyński Dorota Piłakowska-Pietras Stanisław Witek Anna Krasowska 《Journal of surfactants and detergents》2009,12(3):201-207
A homologous series of new surface-active 1,1-bis{[3-(N,N-dimethylamino)ethyl]-amido}alkane-di-N-oxides were synthesized in the reaction of an appropriate diethyl 2-alkylmalonate with N,N-dimethylethylenediamine followed by oxidation with an aqueous solution of hydrogen peroxide. The adsorption isotherms of
their aqueous solutions were measured and evaluated to obtain adsorption parameters: critical micelle concentration (CMC),
surface excess concentration (ΓCMC), equilibrium surface tension at the CMC (γ
CMC), cross-sectional area of the adsorbed surfactant molecule (A
CMC), standard free energies of adsorption and micellization
相似文献
Anna Krasowska (Corresponding author)Email: |
103.
Martyna Ławrywianiec Joanna Smajdor Beata Paczosa-Bator Robert Piech 《Food Analytical Methods》2017,10(12):3825-3835
A voltammetric method for fast and high sensitive determination of Bisphenol A (BPA) using glassy carbon electrode (GC) modified with carbon black nanoparticles (CB) was developed. Cyclic voltammetry study in the 0.1 M phosphates of pH = 7.0 gave single anodic peak at 578 mV. Adsorption-controlled oxidation of BPA was found to be irreversible with the participation of two electrons and two protons. The proposed CB/GC electrode significantly improved the oxidation peak current of BPA compared to the bare electrode. Under the optimum conditions, calibration curve was linear in the concentration of BPA from 0.01 to 3 × 10?6 mol L?1 with the detection limit of 3.4 × 10?9 mol L?1. Moreover, the proposed method was successfully validated by studying the recovery of BPA in commonly available samples: thermal paper (receipt, ticket) and food/beverages packaging. This paper introduces carbon black as a new, perspective material for electrode modification used in voltammetry. 相似文献
104.
The article presents the results of the experimental test on the creep process of AlMgSi alloy wires (series 6xxx) under the
conditions of variable stress. A theoretical analysis of equivalency rheological results of stress and temperature changes
by means of Bayley-Norton function, which describes well the low-temperature aluminum alloys creep, was carried out. Therefore,
the described issue became one-dimensional. On the basis of experimental tests, it has been proved that negative gradients
of stress and temperature may generate three types of rheological behaviour, such as: Temporary decrease of creep speed (type 1), Temporary stop of creep deformation (‘dead’ time)—type 2 and reverse after creep
(type 3).
The applicable nature of tests is placed in overhead power lines, which undergo cyclical stress- and time-dependent operation.
Such a nature of conductor operation creates favourable conditions to decrease creep intensity, whereas its history and value
and speed of stress and temperature lowering decide whether conductor rheological activity loss will take place. The actual
material parameter controlling the conductor rheological behaviour is stress and temperature rheological equivalent. The article
contains exemplary results of current-carrying capacity changes of AlMgSi alloy conductor on a given temperature range, and
the calculations include actual creep characteristic and cumulated rheological inactivity caused by negative gradients of
stress and temperature. 相似文献
105.
Lech Adamus Beata Orchel Artur Szymański A. Pawe? Wojda Ma?gorzata Zwonek 《Information Processing Letters》2009,110(2):44-45
In this note we present a necessary and sufficient condition for a permutation to be t-complementing which is a natural generalization of the well-known result concerning self-complementing permutations. 相似文献
106.
Raz Sarah; Glogowski-Kawamoto Beata; Yu Andrew W.; Kronenberg Mindy E.; Hopkins Tracy L.; Lauterbach Mary D.; Stevens Cynthia P.; Sander Craig J. 《Canadian Metallurgical Quarterly》1998,12(3):459
The goal of this study of 66 twins was to determine whether motor and cognitive functions assessed in early and middle childhood are vulnerable to perinatal hypoxic risk. In an earlier study of 76 infant and toddler twins (S. Raz, F. Shah, & C. Sander, 1996), the authors found that intrapair discrepancy on the Mental Developmental Index, but not on the Psychomotor Developmental Index, of the Bayley Scales of Infant Development was associated with discordance for perinatal hypoxic risk. The twins at lower risk outperformed their higher risk co-twins. In the present study the authors sought to establish in a new sample of preschool and school-age twins whether gaps in performance persist into early and middle childhood. Although the disparity in hypoxic risk between the co-twins was typically moderate, significant intrapair differences were observed on the measure of motor performance. Among the motor abilities examined, skills involving visually guided ballistic arm movements appeared to be the most vulnerable to perinatal risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
The specific properties of silver-nanoparticle immobilized initiator and co-initiators for free radical polymerization were studied. The silver-nanoparticle immobilized benzophenone photoinitiates the free radical polymerization in both UV and visible regions. The photoinitiation ability of Bp-MPCs in visible region suggests a possible two-photon action even at low intensity of an incident light. The co-initiation process by MA-MPCs is more efficient in comparison to the co-initiation observed for corresponding free mercaptoamino acid. This behavior can be attributed to: (i) specific interaction of sulfur electron with surface plasmon electrons that make an electron transfer from mercaptoamino acid to excited electron acceptor more efficient, or (ii) to a locally higher concentration of electron donor (in the ligand shell) in comparison to classical a single-phase solution. 相似文献
108.
The pH influence on photocatalytic decomposition of organic dyes over A11 and P25 titanium dioxide 总被引:5,自引:0,他引:5
Beata Zieli
ska Joanna Grzechulska Ryszard J. Kale
czuk Antoni W. Morawski 《Applied catalysis. B, Environmental》2003,45(4):293-300
The photocatalytic removal (decomposition+adsorption) of four azodyes (Reactive Red 198, Acid Black 1, Acid Blue 7 and Direct Green 99) in water was investigated using Tytanpol A11 (“Police” Chemical Factory, Poland) and Degussa P25 (“Degussa”, Germany) as photocatalysts. The effect of pH of the reaction solution has been examined. The degree of the dye removal in the solution was measured by UV-Vis spectroscopy. Photodecomposition of dye on photocatalyst surface was monitored by FTIR spectroscopy. A11 photocatalyst has lower activity in the reaction of photocatalytic decomposition of organic dyes than Degussa P25. The photocatalytic decomposition of the dyes takes place on the photocatalyst surface at pH=2 while at pH=12 photocatalytic reaction proceeds via photogenerated hydroxyl radicals for both A11 and P25. 相似文献
109.
110.
Cylindrical specimens of experimental lactic acid–glass cements (6 mm high×4 mm diameter) were prepared, matured at 37 °C for one week sealed in their molds, then exposed either to water (pH 6.6) or aqueous lactic acid (pH 2.7) for a further week. Solutions were analyzed by ICP-OES and their pH values recorded. In both solutions, cement specimens were found to release aluminum together with smaller amounts of calcium, sodium, silicon and phosphorus. They also formed soft gels that ICP-OES analysis showed were comprised mainly of aluminum and phosphorus species. These dissolution and gelation processes were accompanied by changes in the pH of the storage media (water to pH 4.9; lactic acid to 4.2). It is concluded that further work is necessary in order to fully characterize the species of aluminum released from these cements. 相似文献