What’s in a name? Rethinking “gifted” to promote equity and excellence

The goal of gifted education is to serve the needs of individuals with high potential and advanced ability. However, the term “gifted” can create barriers in the minds of the public and policymakers, effectively framing these advanced learning opportunities as inequitable and inaccessible. Excellence gaps, or differences in advanced performance among student groups, provide clear indications that systemic changes need to be made in order to provide advanced learning opportunities to all students who need them. To refocus the collective efforts of scholars and stakeholders on promoting equity and excellence, research-based strategies for reducing excellence gaps (e.g., frontloading, universal screening) should be adopted. As best practices in the field shift, so too should terminology. Moving away from words that convey images of fixed abilities (e.g., gifted) and toward terms that acknowledge the dynamic, contextual nature of intelligence and talent is a good start. Suggestions for alternate terminology are discussed.

Conformational features and ionization states of Lys side chains in a protein revealed by the stereo-array isotope labeling (SAIL) method

Although both the hydrophobic aliphatic chain and hydrophilic ζ-amino group of the Lys side chain presumably contribute to the structures and functions of proteins, the dual nature of the Lys residue has not been fully investigated by NMR spectroscopy, due to the lack of appropriate methods to acquire comprehensive information on its long consecutive methylene chain. We describe herein a robust strategy to address the current situation, using various isotope-aided NMR technologies. The feasibility of our approach is demonstrated for the Δ+PHS/V66K variant of Staphylococcal nuclease (SNase), which contains as many as 21 Lys residues, including the engineered Lys-66 with an unusually low pKa of ~5.6. All of the NMR signals for the 21 Lys residues were sequentially and stereo-specifically assigned by using the stereo-array isotope labeled Lys (SAIL-Lys), [U-13C,15N; β2,γ2,δ2,ε3-D4]-Lys. The unambiguously assigned NMR signals for the β-, γ-, δ- and ε-methylene moieties afforded a variety of crucial structural information, which could not be obtained by other methods. For example, the 13Cε signals in the SNase variant, selectively labeled with [ε-13C; ε,ε-D2]-Lys, were ~0.3 ppm up-field shifted in D2O, as compared to those in H2O, except for Lys-66, which showed a ~0.2 ppm up-field shift in D2O. This result indicates that the deuterium-induced up-field shifts of the 13Cε signals depend on the ionization states of the ζ-amino group; i.e., ~ −0.3 ppm for Δδ13Cε [NζD3+-NζH3+] and ~ −0.2 ppm for Δδ13Cε [NζD2-NζH2]. Since the highly sensitive 1D-13C NMR spectrum of a protein selectively labeled with [ε-13C; ε,ε-D2]-Lys shows extremely narrow, well-dispersed 13C signals, the deuterium-induced isotope shifts will be a powerful alternative tool to characterize the ionization states of the Lys ζ-amino groups in larger proteins.

Syntheses and molecular structures of some di(amidino)monosilanes

The syntheses of three different amidinosilanes of the type Me2Si[N=C(Ph)R]2 with R = pyrrolidino, morpholino, and diethylamino and one derivative with the composition R2Si[N=C(Ph)R]2 with R = morpholino are reported. These compounds were prepared in one-pot syntheses including three consecutive steps. All products are analysed by single crystal X-ray diffraction, NMR, and Raman spectroscopy. The Si–N=C–N units of these compounds show characteristic structural features and cause a significant high field shift of the 29Si NMR signals.

Spatial–temporal evolution of photospheric weak-field shifts in solar cycles 21–24

Context. Weak magnetic field elements make a dominant contribution to the total magnetic field on the solar surface. Even so, little is known of their long-term occurrence. Aims. We study the long-term spatial–temporal evolution of the weak-field shift and skewness of the distribution of photospheric magnetic field values during solar cycles 21−24 in order to clarify the role and relation of the weak field values to the overall magnetic field evolution. Methods. We used Wilcox Solar Observatory (WSO) and the Synoptic Optical Long-term Investigations of the Sun Vector SpectroMagnetograph synoptic maps to calculate weak-field shifts for each latitude bin of each synoptic map, and thereby constructed a time–latitude butterfly diagram for shifts. We also calculated butterfly diagrams for skewness for all field values and for weak field values only. Results. The weak-field shifts and (full-field) skewness depict a similar spatial–temporal solar cycle evolution to that of the large-scale surface magnetic field. The field distribution has a systematic non-zero weak-field shift and a large skewness already at (and after) the emergence of the active region, even at the highest resolution. We find evidence for coalescence of opposite-polarity fields during the surge evolution. This is clearly more effective at the supergranulation scale. However, a similar dependence of magnetic field coalescence on spatial resolution was not found in the unipolar regions around the poles. Conclusions. Our results give evidence for the preference of even the weakest field elements toward the prevailing magnetic polarity since the emergence of an active region, and for a systematic coalescence of stronger magnetic fields of opposite polarities to produce weak fields during surge evolution and at the poles. We also find that the supergranulation process is reduced or turned off in the unipolar regions around the poles. These observations improve the understanding not only of the development of the weakest magnetic field elements, but also of the dynamics of magnetic fields at large, and even of processes below the solar surface.

Расчеты релятивистских, корреляционных, ядерных и квантово-электродинамических поправок к энергии и потенциалу ионизации основного состояния гелиеподобных ионов

In this work, nonrelativistic and relativistic variational calculations of the energies and ionization potentials of the ground state of helium-like ions for the nuclear charges in the range Z = 2 − 20 were performed.the leading corrections to the total energy were calculated including the contribution of electronic correlations, relativistic and quantum-electrodynamic (QED) corrections, and the contributions of the finite size ofnucleus (field shift) and the finite mass of the nucleus (recoil effect). Relativistic сalculations of the wave functions were performed using the Dirac-Coulomb-Breit (DCB) Hamiltonian.

Изотопические сдвиги уровней энергии в гелиеподобных многозарядных ионах

The precision calculations of the isotope shifts of the $n = 1$, $n = 2$ energy levels and the corresponding transition energies in helium-like highly charged ions are performed. The total isotope shift is mainly determined by a sum of the field and mass shifts. The field shift is calculated by the configuration-interaction Dirac-Fock-Sturm method. The quantum electrodynamics corrections to this contribution are taken into account approximately by using the corresponding one-electron formulas. The calculation of the mass shift is performed within the framework of the Breit approximation and includes the quantum electrodynamics contributions, which become very significant for heavy ions. For the thorium and uranium ions the nuclear polarization and deformation corrections are taken into account.