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91.
Dr. Brian P. Corbet J. Malte Schlüter Elena R. Cotroneo Dr. Stefano Crespi Prof. Dr. Nadja A. Simeth 《European journal of organic chemistry》2023,26(1):e202201140
Light-responsive molecules have seen a major advance in modulating biological functions in recent years. Especially photoswitches are highly attractive building blocks due to the reversible nature of their light-mediated reactivity. They are frequently used to affect both the properties of small bioactive compounds and biomacromolecules if incorporated suitably. Despite their success in a plethora of applications, only a limited set of photochromic core structures is routinely employed and a large number of photochromic couples are under-investigated in biological context. Broadening the toolbox of photoswitches available to modulate biological activity would open new avenues and unlock the full potential of photoswitchable molecules for biological studies. In this work, we explore the photochemical and thermal properties of the dihydroazulene/vinylheptafulvene photochromic couple as peptide conjugates in aqueous environment. 相似文献
92.
Woderer S Henninger N Garthe CD Kloetzer HM Hajnsek M Kamecke U Gretz N Kraenzlin B Pill J 《Analytica chimica acta》2007,581(1):7-12
Glucose monitoring is of importance for success of complex therapeutic interventions in diabetic patients. Its impact on treatment and glycemic control is demonstrated in large clinical trials. Up to eight blood glucose measurements per day are recommended. Notwithstanding, a substantial number of diabetic patients cannot or will not monitor their blood glucose appropriately. Considerable progress in control of disturbed metabolism in diabetic patients can be expected by continuous glucose monitoring. The aim of the study was to evaluate the performance of a new amperometric glucose oxidase-based glucose sensor in vitro and in vivo after subcutaneous implantation into rats.For in vitro testing current output of sensors was measured by exposure to increasing and decreasing glucose concentrations up to 472 mg dL−1 over a time period of 7 days. After subcutaneous implantation of sensors into interscapular region of male rats glucose in interstitial fluid was evaluated and compared to glucose in arterial blood up to 7 days. Hyper- and hypoglycaemia were induced by intravenous application of glucose and insulin, respectively. Current of each implanted sensor was converted into glucose concentration using the first blood glucose measurement only.A change of current with glucose of 0.35 nA mg−1 dL−1 indicates high sensitivity of the sensor in vitro. The response time (90% of steady state) was calculated by approximately 60 s. Test strips for blood glucose measurement as reference for sensor readings was found as an appropriate and rapidly available method in rats by comparison with established hexokinase method in an automated lab analyzer with limits of agreement of +32.8 and −25.7 mg dL−1 in Bland-Altman analysis. In normo- and hypoglycaemic range sensor readings in interstitial fluid correlated well with blood glucose measurements whereas hyperglycaemia was not reflected by the sensor completely when blood glucose was changing rapidly.The data given characterize a sensor with high sensitivity, long term stability and short response time. A single calibration of the sensor is required only in measurement periods up to 7 days. The findings demonstrate that the sensor is a highly promising candidate for assessment in humans. 相似文献
93.
A. Algora J. L. Taín A. B. Perez B. Rubio J. Agramunt L. Caballero E. Nácher A. Krasznahorkay M. D. Hunyadi J. Gulyás A. Vitéz J. Äystö H. Penttilä S. Rinta-Antila I. Moore T. Eronen A. Jokinen A. Nieminen J. Hakala P. Karvonen A. Kankainen U. Hager T. Sonoda K. Burkard W. Hüller L. Batist W. Gelletly T. Yoshida A. L. Nichols A. Sonzogni 《The European physical journal. Special topics》2007,150(1):383-384
94.
Michael E. Böttcher Patrizia Geprägs Nadja Neubert Katja von Allmen Chloé Pretet Elias Samankassou 《Isotopes in environmental and health studies》2013,49(3):457-463
In this study, we present the first experimental results for stable barium (Ba) isotope (137Ba/134Ba) fractionation during low-temperature formation of the anhydrous double carbonate BaMn[CO3]2. This investigation is part of an ongoing work on Ba fractionation in the natural barium cycle. Precipitation at a temperature of 21±1°C leads to an enrichment of the lighter Ba isotope described by an enrichment factor of?0.11±0.06‰ in the double carbonate than in an aqueous barium-manganese(II) chloride/sodium bicarbonate solution, which is within the range of previous reports for synthetic pure BaCO 3 (witherite) formation. 相似文献
95.
Nadja M��ller 《Transport in Porous Media》2011,87(2):367-383
The relative permeability of carbon dioxide (CO2) to brine influences the injectivity and plume migration when CO2 is injected in a reservoir for CO2 storage or enhanced oil recovery (EOR) purposes. It is common practice to determine the relative permeability of a fluid by means of laboratory measurements. Two principal approaches are used to obtain a relative permeability data: steady state and unsteady state. Although CO2 has been employed in enhanced oil recovery, not much data can be found in the open literature. The few studies available report wide ranges for CO2 relative permeability in typical sedimentary rocks such as Berea sandstone, dolomite, and others. The experimental setups vary for each study, employing steady and unsteady state approaches, different experimental parameters such as temperature, pressure, rock type, etc. and various interpretation methods. Hence, it is inherently difficult to compare the data and determine the origin of differences. It is evident that more experiments are needed to close this knowledge gap on relative permeability. This article concludes that standards for lab measurements need to be defined a. to establish a reliable CO2-brine relative permeability measurement method that can be repeated under the same conditions in any lab and b. to enable comparison of the data to accurately predict the well injection and fluid migration behavior in the reservoir. 相似文献
96.
This article considers the inverse absolute and the inverse vertex 1-center location problems with uniform cost coefficients on a tree network T with n+1 vertices. The aim is to change (increase or reduce) the edge lengths at minimum total cost with respect to given modification bounds such that a prespecified vertex s becomes an absolute (or a vertex) 1-center under the new edge lengths. First an O(nlogn) time method for solving the height balancing problem with uniform costs is described. In this problem the height of two given rooted trees is equalized by decreasing the height of one tree and increasing the height of the second rooted tree at minimum cost. Using this result a combinatorial O(nlogn) time algorithm is designed for the uniform-cost inverse absolute 1-center location problem on tree T. Finally, the uniform-cost inverse vertex 1-center location problem on T is investigated. It is shown that the problem can be solved in O(nlogn) time if all modified edge lengths remain positive. Dropping this condition, the general model can be solved in O(rvnlogn) time where the parameter rv is bounded by ⌈n/2⌉. This corrects an earlier result of Yang and Zhang. 相似文献
97.
Nadja Hvala Mario Zec Stanko Strm?nik 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(6):587-605
This article deals with non-linear model parameter estimation from experimental data. As for non-linear models a rigorous identifiability analysis is difficult to perform, parameter estimation is performed in such a way that uncertainty in the estimated parameter values is represented by the range of model use results when the model is used for a certain purpose. Using this approach, the article presents a simulation study where the objective is to discover whether the estimation of model parameters can be improved, so that a small enough range of model use results is obtained. The results of the study indicate that from plant measurements available for the estimation of model parameters, it is possible to extract data that are important for the estimation of model parameters relative to a certain model use. If these data are improved by a proper measurement campaign (e.g. proper choice of measured variables, better accuracy, higher measurement frequency) it is to be expected that a valid model for a certain model use will be obtained. The simulation study is performed for an activated sludge model from wastewater treatment, while the estimation of model parameters is done by Monte Carlo simulation. 相似文献
98.
Algora A Jordan D Taín JL Rubio B Agramunt J Perez-Cerdan AB Molina F Caballero L Nácher E Krasznahorkay A Hunyadi MD Gulyás J Vitéz A Csatlós M Csige L Aysto J Penttilä H Moore ID Eronen T Jokinen A Nieminen A Hakala J Karvonen P Kankainen A Saastamoinen A Rissanen J Kessler T Weber C Ronkainen J Rahaman S Elomaa V Rinta-Antila S Hager U Sonoda T Burkard K Hüller W Batist L Gelletly W Nichols AL Yoshida T Sonzogni AA Peräjärvi K 《Physical review letters》2010,105(20):202501
The β feeding probability of (102,104,105,106,107)Tc, 105Mo, and 101Nb nuclei, which are important contributors to the decay heat in nuclear reactors, has been measured using the total absorption technique. We have coupled for the first time a total absorption spectrometer to a Penning trap in order to obtain sources of very high isobaric purity. Our results solve a significant part of a long-standing discrepancy in the γ component of the decay heat for 239Pu in the 4-3000 s range. 相似文献
99.
Michael E. Böttcher Nadja Neubert Katja von Allmen Elias Samankassou Thomas F. Nägler 《Isotopes in environmental and health studies》2018,54(3):324-335
In this study, we present the experimental results for stable barium (Ba) isotope fractionation (137Ba/134Ba) during the transformation of aragonite (CaCO3) and gypsum (CaSO4·2H2O) in Ba-bearing aqueous solution to witherite (BaCO3) and barite (BaSO4), respectively. The process was studied at three temperatures between 4 and 60?°C. In all cases, the transformation leads to a relative enrichment of the lighter 134Ba isotope in the solid compared to the aqueous solution, with 137/134Ba enrichment factors between –0.11 and ?0.17?‰ for BaCO3, and –0.21 and –0.26?‰ for BaSO4. The corresponding mass-dependent 138/134Ba enrichment factors are ?0.15 to –0.23?‰ for BaCO3, and –0.28 to –0.35?‰ for BaSO4. The magnitude of isotope fractionation is within the range of recent reports for witherite and barite formation, as well as trace Ba incorporation into orthorhombic aragonite, and no substantial impact of temperature can be found between 4 and 80?°C. In previous studies, ion (de)solvation has been suggested to impact both the crystallization process of Ba-bearing solids and associated Ba isotope fractionation. Precipitation experiments of BaSO4 and BaCO3 using an methanol-containing aqueous solution indicate only a minor effect of ion and crystal surface (de)solvation on the overall Ba isotope fractionation process. 相似文献
100.
Leonardo A. M. Souza Nadja K. Bernardes Romeu RossiJr. 《Brazilian Journal of Physics》2017,47(2):157-166
In this work, we study the so-called quantitative complementarity quantities. We focus in the following physical situation: two qubits (q A and q B ) are initially in a maximally entangled state. One of them (q B ) interacts with a N-qubit system (R). After the interaction, projective measurements are performed on each of the qubits of R, in a basis that is chosen after independent optimization procedures: maximization of the visibility, the concurrence, and the predictability. For a specific maximization procedure, we study in detail how each of the complementary quantities behave, conditioned on the intensity of the coupling between q B and the N qubits. We show that, if the coupling is sufficiently “strong,” independent of the maximization procedure, the concurrence tends to decay quickly. Interestingly enough, the behavior of the concurrence in this model is similar to the entanglement dynamics of a two qubit system subjected to a thermal reservoir, despite that we consider finite N. However, the visibility shows a different behavior: its maximization is more efficient for stronger coupling constants. Moreover, we investigate how the distinguishability, or the information stored in different parts of the system, is distributed for different couplings. 相似文献