Proton-translocating NADH:ubiquinone oxidoreductase (complex I) is the largest and least understood enzyme of the respiratory chain. Complex I from bovine mitochondria consists of more than forty ...different polypeptides. Subunit PSST has been suggested to carry iron-sulfur center N-2 and has more recently been shown to be involved in inhibitor binding. Due to its pH-dependent midpoint potential, N-2 has been proposed to play a central role both in ubiquinone reduction and proton pumping. To obtain more insight into the functional role of PSST, we have analyzed site-directed mutants of conserved acidic residues in the PSST homologous subunit of the obligate aerobic yeast Yarrowia lipolytica. Mutations D136N and E140Q provided functional evidence that conserved acidic residues in PSST play a central role in the proton translocating mechanism of complex I and also in the interaction with the substrate ubiquinone. When Glu89, the residue that has been suggested to be the fourth ligand of iron-sulfur center N-2 was changed to glutamine, alanine, or cysteine, the EPR spectrum revealed an unchanged amount of this redox center but was shifted and broadened in the gzregion. This indicates that Glu89 is not a ligand of N-2. The results are discussedin the light of structural similarities to the homologous NiFe hydrogenases.
A cosmic-ray database update: CRDB v4.1 Maurin, David; Ahlers, Markus; Dembinski, Hans ...
The European physical journal. C, Particles and fields,
10/2023, Letnik:
83, Številka:
10
Journal Article
Recenzirano
Odprti dostop
The cosmic-ray database, CRDB, has been gathering cosmic-ray data for the community since 2013. We present a new release, CRDB v4.1, providing many new quantities and data sets, with several ...improvements made on the code and web interface, and with new visualisation tools. CRDB relies on the MySQL database management system, jquery and table-sorter libraries for queries and sorting, and PHP web pages and AJAX protocol for displays. A REST interface enables user queries from command line or scripts. A new (pip-installable) CRDB python library is developed and extensive jupyter notebook examples are provided. This release contains cosmic-ray dipole anisotropy data, high-energy
p
¯
/
p
upper limits, some unpublished LEE and AESOP lepton time series, many more ultra-high energy data, and a few missing old data sets. It also includes high-precision data from the last three years, in particular the hundreds of thousands AMS-02 and PAMELA data time series (time-dependent plots are now enabled). All these data are shown in a gallery of plots, which can be easily reproduced from the public notebook examples. CRDB contains 316,126 data points from 504 publications, in 4111 sub-experiments from 131 experiments.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The changes in Gibbs energy were evaluated for the atomic configurations resulting after different diffusional processes, in order to detect the mechanisms that are responsible for stabilisation and ...rubber-like behaviour. The energies and the proposed atom interchanges were compared with the experimental evidence. The influence of the changes in short- and long-range order was evaluated in the binary and ternary Cu-based alloys.
An initial study to develop a numerical tool using computational fluid dynamics (CFD) methods for investigating the potential of disease transmission in commercial aircraft is completed. To gain ...insight of the general airflow pattern, a detailed CFD model of a small section in the passenger cabin of a B767-300 passenger cabin was built and a Reynolds-averaged Navier-Stokes (RANS) simulation was performed. By comparing with the available test data, the RANS simulation substantially underpredicted the turbulence intensity, especially in and around the breathing zone. A separate large eddy simulation (LES) was conducted to obtain a more realistic turbulent energy transport in a generic cabin model. The LES predicted turbulence level is in fairly good agreement with the test data. Based on the LES results, the k and e equations used in the RANS simulation were modified by using a special user subroutine. A RANS simulation with adjusted turbulence was then employed to simulate the dispersion of airborne pathogen in the detailed passenger cabin model. These adjustments allow for the simulation ofdisease transmission using less than 1/100 of the computing hardware resources required for an equivalent LES of airflow and particle transport.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
We present a search for a neutrino signal from dark matter self-annihilations in the Milky Way using the IceCube Neutrino Observatory (IceCube). In 1005 days of data we found no significant excess of ...neutrinos over the background of neutrinos produced in atmospheric air showers from cosmic ray interactions. We derive upper limits on the velocity averaged product of the dark matter self-annihilation cross section and the relative velocity of the dark matter particles
⟨
σ
A
v
⟩
. Upper limits are set for dark matter particle candidate masses ranging from 10 GeV up to 1 TeV while considering annihilation through multiple channels. This work sets the most stringent limit on a neutrino signal from dark matter with mass between 10 and 100 GeV, with a limit of
1.18
·
10
-
23
cm
3
s
-
1
for 100 GeV dark matter particles self-annihilating via
τ
+
τ
-
to neutrinos (assuming the Navarro–Frenk–White dark matter halo profile).
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
By adding small amounts of ternary elements Ge, Si or Sn, it is possible to raise the martensitic transformation temperature
M
S of binary B2 ordered Cu–Zn towards room temperature. Several poly and ...single crystal ternary alloys have been studied using resistivity and calorimetric measurements, tensile experiments and optical observations. The influence of the composition and thermomechanical pretreatment on the martensitic transformation has been analyzed. It is shown that the increase in the transformation temperature at a constant electron concentration favors competing decomposition mechanisms.
Genes playing a role in carcinogenesis have often been identified through analysis of recurrent chromosomal rearrangements. Although such rearrangements are well known in leukemias, lymphomas, and ...sarcomas, they have not been well characterized in carcinomas. The authors applied bioinformatics techniques to identify candidate oncogenic chromosomal changes based on analysis of outlier gene expression. The authors determined that two ETS transcription factors, ERG and ETV1 were outliers in prostate cancer. The group reports recurrent fusions of the 5' untranslated region of theTMPRSS2 gene to ERG and ETV1 in the majority of prostate cancer samples containing the outlier expression. In cell lines containing the fusion gene, androgen appears to play a role in mediating ETS overexpression. This fusion gene product may play an important role in the development, diagnosis, and treatment of prostate cancer.
The atom movements during the martensitic transformation are described by a combination of two shears: a long-wave primary and a secondary shuffle type shear which occur simultaneously. The primary ...and part of the secondary shear are equivalent to the Bain distortion, and the rest of the secondary shear corresponds to the lattice invariant shear of the phenomenological theories. This description permits us to obtain information on the multiplicity of the transformation-retransformation paths. It is shown that the shape-memory alloys have a single possible path when the matrix phase possesses long-range order. The selection of the activated shear systems can be correlated with their resistance against small displacements, given by the corresponding elastic constants. This permits us to classify and interpret the crystallography of a large body of martensitic transformations.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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