487 research outputs found
Lipopolysaccharide -mediated resistance to host antimicrobial peptides and hemocytederived reactive-oxygen species are the major Providencia alcalifaciens virulence factors in Drosophila melanogaster
The use of indigenous knowledge in development: problems and challenges
The use of indigenous knowledge has been seen by many as an alternative way of promoting development in poor rural communities in many parts of the world. By reviewing much of the recent work on indigenous knowledge, the paper suggests that a number of problems and tensions has resulted in indigenous knowledge not being as useful as hoped for or supposed. These include problems emanating from a focus on the (arte)factual; binary tensions between western science and indigenous knowledge systems; the problem of differentiation and power relations; the romanticization of indigenous knowledge; and the all too frequent decontextualization of indigenous knowledge
Довіра до поліції, як основний принцип взаємодії з громадськістю
Баранова, Ц. С. Довіра до поліції, як основний принцип взаємодії з громадськістю / Баранова Ц. С., Шака М. В. // Взаємодія поліції з населенням на засадах партнерства: сучасний стан та перспективи розвитку: матеріали наук.-практ. круглий стіл (м. Одеса, 25 листоп. 2021 р.) / МВС України, Одес. держ. ун-т внутр. справ, Каф. адмін. діял. поліції. - Одеса: ОДУВС, 2021. - С. 20-22.Зазначено, що довіра є однією із фундаментальних основ партнерства, налагодження якого сприяє, з одного боку, підвищенню ефективності виконання працівниками поліції своїх обов’язків із охорони громадського порядку, а з другого – відчуттю захищеності громадян.It is noted that trust is one of the fundamental foundations of partnership, the establishment of which contributes, on the one hand, to increasing the efficiency of the police officers' performance of their duties to protect public order, and on the other hand, to the feeling of security of citizens.Отмечено, что доверие является одной из фундаментальных основ партнерства, налаживание которого способствует, с одной стороны, повышению эффективности выполнения работниками полиции своих обязанностей по охране общественного порядка, а с другой – ощущению защищенности граждан
Comparison of dynamical decoupling protocols for a nitrogen-vacancy center in diamond
We perform a detailed theoretical-experimental study of the dynamical
decoupling (DD) of the nitrogen-vacancy (NV) center in diamond. We investigate
the DD sequences applied to suppress the dephasing of the electron spin of the
NV center induced by the coupling to a spin bath composed of the substitutional
nitrogen atoms. The decoupling efficiency of various DD schemes is studied,
including both periodic and periodic pulse sequences. For ideal control pulses,
we find that the DD protocols with the Carr-Purcell-Meiboom-Gill (CPMG) timing
of the pulses provides best performance. We show that, as the number of control
pulses increases, the decoupling fidelity scaling differs qualitatively from
the predictions of the Magnus expansion, and explain the origin of this
difference. In particular, more advanced symmetrized or concatenated protocols
do not improve the DD performance. Next, we investigate the impact of the
systematic instrumental pulse errors in different periodic and aperiodic pulse
sequences. The DD protocols with the single-axis control do not preserve all
spin components in the presence of the pulse errors, and the two-axis control
is needed. We demonstrate that the two-axis control sequence with the CPMG
timing is very robust with respect to the pulse errors. The impact of the pulse
errors can be diminished further by symmetrizing this protocol. For all
protocols studied here, we present a detailed account of the pulse error
parameters which make strongest impact on the DD performance. In conclusion, we
give specific recommendations about choosing the decoupling protocol for the
system under investigation.Comment: 16 pages, 11 figure
Bang-Bang control of a qubit coupled to a quantum critical spin bath
We analytically and numerically study the effects of pulsed control on the
decoherence of a qubit coupled to a quantum spin bath. When the environment is
critical, decoherence is faster and we show that the control is relatively more
effective. Two coupling models are investigated, namely a qubit coupled to a
bath via a single link and a spin star model, yielding results that are similar
and consistent.Comment: 10 pages, 4 figures, replaced with published versio
High dimensional and high resolution pulse sequences for backbone resonance assignment of intrinsically disordered proteins
Four novel 5D (HACA(N)CONH, HNCOCACB, (HACA)CON(CA)CONH, (H)NCO(NCA)CONH), and one 6D ((H)NCO(N)CACONH) NMR pulse sequences are proposed. The new experiments employ non-uniform sampling that enables achieving high resolution in indirectly detected dimensions. The experiments facilitate resonance assignment of intrinsically disordered proteins. The novel pulse sequences were successfully tested using δ subunit (20 kDa) of Bacillus subtilis RNA polymerase that has an 81-amino acid disordered part containing various repetitive sequences
Amino acid recognition for automatic resonance assignment of intrinsically disordered proteins
Targeting Melanoma Metastasis and Immunosuppression with a New Mode of Melanoma Inhibitory Activity (MIA) Protein Inhibition
Melanoma is the most aggressive form of skin cancer, with fast progression and early dissemination mediated by the melanoma inhibitory activity (MIA) protein. Here, we discovered that dimerization of MIA is required for functional activity through mutagenesis of MIA which showed the correlation between dimerization and functional activity. We subsequently identified the dodecapeptide AR71, which prevents MIA dimerization and thereby acts as a MIA inhibitor. Two-dimensional nuclear magnetic resonance (NMR) spectroscopy demonstrated the binding of AR71 to the MIA dimerization domain, in agreement with in vitro and in vivo data revealing reduced cell migration, reduced formation of metastases and increased immune response after AR71 treatment. We believe AR71 is a lead structure for MIA inhibitors. More generally, inhibiting MIA dimerization is a novel therapeutic concept in melanoma therapy
13C-direct detected NMR experiments for the sequential J-based resonance assignment of RNA oligonucleotides
We present here a set of 13C-direct detected NMR experiments to facilitate the resonance assignment of RNA oligonucleotides. Three experiments have been developed: (1) the (H)CC-TOCSY-experiment utilizing a virtual decoupling scheme to assign the intraresidual ribose 13C-spins, (2) the (H)CPC-experiment that correlates each phosphorus with the C4′ nuclei of adjacent nucleotides via J(C,P) couplings and (3) the (H)CPC-CCH-TOCSY-experiment that correlates the phosphorus nuclei with the respective C1′,H1′ ribose signals. The experiments were applied to two RNA hairpin structures. The current set of 13C-direct detected experiments allows direct and unambiguous assignment of the majority of the hetero nuclei and the identification of the individual ribose moieties following their sequential assignment. Thus, 13C-direct detected NMR methods constitute useful complements to the conventional 1H-detected approach for the resonance assignment of oligonucleotides that is often hindered by the limited chemical shift dispersion. The developed methods can also be applied to large deuterated RNAs
The S4–S5 Linker Acts as a Signal Integrator for hERG K+ Channel Activation and Deactivation Gating
Human ether-à-go-go-related gene (hERG) K+ channels have unusual gating kinetics. Characterised by slow activation/deactivation but rapid inactivation/recovery from inactivation, the unique gating kinetics underlie the central role hERG channels play in cardiac repolarisation. The slow activation and deactivation kinetics are regulated in part by the S4–S5 linker, which couples movement of the voltage sensor domain to opening of the activation gate at the distal end of the inner helix of the pore domain. It has also been suggested that cytosolic domains may interact with the S4–S5 linker to regulate activation and deactivation kinetics. Here, we show that the solution structure of a peptide corresponding to the S4–S5 linker of hERG contains an amphipathic helix. The effects of mutations at the majority of residues in the S4–S5 linker of hERG were consistent with the previously identified role in coupling voltage sensor movement to the activation gate. However, mutations to Ser543, Tyr545, Gly546 and Ala548 had more complex phenotypes indicating that these residues are involved in additional interactions. We propose a model in which the S4–S5 linker, in addition to coupling VSD movement to the activation gate, also contributes to interactions that stabilise the closed state and a separate set of interactions that stabilise the open state. The S4–S5 linker therefore acts as a signal integrator and plays a crucial role in the slow deactivation kinetics of the channel
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