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排序方式: 共有143条查询结果,搜索用时 15 毫秒
31.
Enrique Gil de Montes Dr. Alena Istrate Dr. Claudio D. Navo Dr. Ester Jiménez-Moreno Emily A. Hoyt Dr. Francisco Corzana Prof. Inmaculada Robina Dr. Gonzalo Jiménez-Osés Dr. Antonio J. Moreno-Vargas Dr. Gonçalo J. L. Bernardes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6255-6259
An azanorbornadiene bromovinyl sulfone reagent for cysteine-selective bioconjugation has been developed. Subsequent reaction with dipyridyl tetrazine leads to bond cleavage and formation of a pyrrole-linked conjugate. The latter involves ligation of the tetrazine to the azanorbornadiene-tagged protein through inverse electron demand Diels–Alder cycloaddition with subsequent double retro-Diels–Alder reactions to form a stable pyrrole linkage. The sequence of site-selective bioconjugation followed by bioorthogonal bond cleavage was efficiently employed for the labelling of three different proteins. This method benefits from easy preparation of these reagents, selectivity for cysteine, and stability after reaction with a commercial tetrazine, which has potential for the routine preparation of protein conjugates for chemical biology studies. 相似文献
32.
Özge Pala Dirk J Vriens Jac AM Vennix 《The Journal of the Operational Research Society》2015,66(4):593-601
Escalation of commitment, the tendency of decision makers to keep on investing in losing courses of action, has been shown to be a costly decision bias that affects many areas of decision making. Even though escalation is a widely studied phenomenon, there has been comparatively little research on how to avoid this bias. The present study focuses on de-escalation of commitment and proposes that causal loop diagrams (CLDs) can help to decrease escalating commitment to a failing course of action. By means of an experiment, this study shows that using a CLD decreases escalation tendencies. 相似文献
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A fully automatic apparatus for thermal analysis of crystallization from solution and metastable zone width determinations 总被引:1,自引:0,他引:1
Carlos E. S. Bernardes Manuel E. Minas da Piedade 《Journal of Thermal Analysis and Calorimetry》2010,100(2):493-500
This work describes the development of a fully automatic apparatus to perform crystallization studies and metastable zone
width (MSW) determinations using the polythermal method. Heating and cooling ramps, and isothermal steps can be carried out,
while continuously monitoring the mixture inside the crystallization vessel, with temperature and turbidity sensors. These
allow the onsets of crystallization or of complete dissolution of the solute to be detected. Programmed dilutions of the mixture
under study can also be automatically performed, so that different concentrations can be studied in a given experiment. The
apparatus was tested by using the ammonium chloride–water system. The results indicated that it is capable of reproducing
the equilibrium solubilities of ammonium chloride in water, independently determined by the residue mass method, with an average
deviation of 0.6 K. The obtained MSW and the kinetic parameters for the crystallization process showed deviations from the
literature data, which are typical of these studies when nucleation is not induced by the addition of crystalline seeds. 相似文献
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García Ruano JL Gamboa AE Gutiérrez LG Martín Castro AM Rodríguez Ramos JH Yuste F 《Organic letters》2000,2(6):733-736
A new kind of chiral dienophiles, cyclic vinyl-p-tolylsulfilimines (2a and 2b), were obtained from the corresponding (Z)-sulfinylacrylonitriles with HBF(4) and methanol. The asymmetric Diels-Alder reaction of optically pure 2a with cyclopentadiene under mild thermal or catalyzed conditions afforded only the endo-4a adduct with complete endo and pi-facial selectivities. The ability of the sulfilimine moiety to enhance the dienophilic reactivity of the double bond is similar to that of the sulfinyl group. 相似文献
38.
Positivity - Consider a compact convex subset X of R n (n ≥ 2) with non-empty interior and let H(X) be the set of all homeomorphisms from X onto X endowed with the supremum metric. We are... 相似文献
39.
María Navarro-Cceres Marcelo Caetano Gilberto Bernardes Mercedes Snchez-Barba Javier Merchn Snchez-Jara 《Entropy (Basel, Switzerland)》2020,22(11)
In tonal music, musical tension is strongly associated with musical expression, particularly with expectations and emotions. Most listeners are able to perceive musical tension subjectively, yet musical tension is difficult to be measured objectively, as it is connected with musical parameters such as rhythm, dynamics, melody, harmony, and timbre. Musical tension specifically associated with melodic and harmonic motion is called tonal tension. In this article, we are interested in perceived changes of tonal tension over time for chord progressions, dubbed tonal tension profiles. We propose an objective measure capable of capturing tension profile according to different tonal music parameters, namely, tonal distance, dissonance, voice leading, and hierarchical tension. We performed two experiments to validate the proposed model of tonal tension profile and compared against Lerdahl’s model and MorpheuS across 12 chord progressions. Our results show that the considered four tonal parameters contribute differently to the perception of tonal tension. In our model, their relative importance adopts the following weights, summing to unity: dissonance (0.402), hierarchical tension (0.246), tonal distance (0.202), and voice leading (0.193). The assumption that listeners perceive global changes in tonal tension as prototypical profiles is strongly suggested in our results, which outperform the state-of-the-art models. 相似文献
40.
Toledano P Figueiredo Neto AM de Sant'Ana ZA 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》2000,61(1):486-492
Experimental investigations of lyotropic cholesterics fluids are presented which show that changes in the shape anisotropy and chirality of the micellar population determine the topology of the temperature-concentration phase diagrams. For given amounts of the substances which induce the chirality and modify the shape anisotropy of the micelles, two distinct biaxial cholesteric phases are disclosed in the phase diagrams. This is interpreted in the framework of the catastrophe theory of phase transitions. 相似文献