871 results on '"P. Sobota"'
Search Results
2. Terahertz-induced tunnel ionization drives coherent Raman-active phonon in Bismuth
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Cheng, Bing, Kramer, Patrick L., Trigo, Mariano, Liu, Mengkun, Reis, David A., Shen, Zhi-Xun, Sobota, Jonathan A., and Hoffmann, Matthias. C.
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Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Materials Science - Abstract
Driving coherent lattice motion with THz pulses has emerged as a novel pathway for achieving dynamic stabilization of exotic phases that are inaccessible in equilibrium quantum materials. In this work, we present a previously unexplored mechanism for THz excitation of Raman-active phonons in semimetals. We show that intense THz pulses centered at 1 THz can excite the Raman-active $A_{1g}$ phonon mode at 2.9 THz in a bismuth film. We rule out the possibilities of the phonon being excited through conventional anharmonic coupling to other modes or via a THz sum frequency process. Instead, we demonstrate that the THz-driven tunnel ionization provides a plausible means of creating a displacive driving force to initiate the phonon oscillations. Our work highlights a new mechanism for exciting coherent phonons, offering potential for dynamic control over the electronic and structural properties of semimetals and narrow-band semiconductors on ultrafast timescales., Comment: main text + SI, 12 pages, 10 figures
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- 2024
3. Complemented subspaces of Banach spaces $C(K\times L)$
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Plebanek, Grzegorz, Rondoš, Jakub, and Sobota, Damian
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Mathematics - Functional Analysis ,Primary: 46B20, 46E15. Secondary: 28A33, 46B26 - Abstract
We prove that, for every compact spaces $K_1,K_2$ and compact group $G$, if both $K_1$ and $K_2$ map continuously onto $G$, then the Banach space $C(K_1 \times K_2)$ contains a complemented subspace isometric to the Banach space $C(G)$. Consequently, $C(K_1\times K_2)$ contains a complemented copy of $C([0,1])$ for every non-scattered $K_1,K_2$. Also, answering a question of Alspach and Galego, we get that $C(\beta\omega\times\beta\omega)$ contains a complemented copy of $C([0,1]^\kappa)$ for every cardinal number $1\le\kappa\le{\mathfrak c}$ and hence a complemented copy of $C(K)$ for every metric compact space $K$. On the other hand, for the pointwise topology, we show that $C_p(\beta\omega\times\beta\omega)$ contains no complemented copy of $C_p(2^\omega)$., Comment: 18 pages; second version
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- 2024
4. Continuous operators from spaces of Lipschitz functions
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Bargetz, Christian, Kąkol, Jerzy, and Sobota, Damian
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Mathematics - Functional Analysis ,Mathematics - General Topology - Abstract
We study the existence of continuous (linear) operators from the Banach spaces $\mbox{Lip}_0(M)$ of Lipschitz functions on infinite metric spaces $M$ vanishing at a distinguished point and from their predual spaces $\mathcal{F}(M)$ onto certain Banach spaces, including $C(K)$-spaces and the spaces $c_0$ and $\ell_1$. For pairs of spaces $\mbox{Lip}_0(M)$ and $C(K)$ we prove that if they are endowed with topologies weaker than the norm topology, then usually no continuous (linear or not) surjection exists between those spaces. It is also showed that if a metric space $M$ contains a bilipschitz copy of the unit sphere $S_{c_0}$ of the space $c_0$, then $\mbox{Lip}_0(M)$ admits a continuous operator onto $\ell_1$ and hence onto $c_0$. Using this, we provide several conditions for a space $M$ implying that $\mbox{Lip}_0(M)$ is not a Grothendieck space. Finally, we obtain a new characterization of the Schur property for Lipschitz-free spaces: a space $\mathcal{F}(M)$ has the Schur property if and only if for every discrete metric space $N$ with cardinality $d(M)$ the spaces $\mathcal{F}(M)$ and $\mathcal{F}(N)$ are weakly sequentially homeomorphic., Comment: 26 pages, comments are welcome!
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- 2024
5. Band structure of Bi surfaces formed on Bi2Se3 upon exposure to air
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Gauthier, Alexandre, Sobota, Jonathan A., Gauthier, Nicolas, Rotundu, Costel R., Shen, Zhi-Xun, and Kirchmann, Patrick S.
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Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Bi$_2$Se$_3$ has been the focus of intense interest over the past decade due to its topological properties. Bi surfaces are known to form on Bi$_2$Se$_3$ upon exposure to atmosphere, but their electronic structure has not been investigated. We report band structure measurements of such Bi surfaces using angle-resolved photoemission spectroscopy. Measured spectra can be well explained by the band structure of a single bilayer of Bi on Bi$_2$Se$_3$, and show that Bi surfaces consistently dominate the photoemission signal for air exposure times of at least 1 hour. These results demonstrate that atmospheric effects should be taken into consideration when identifying two-dimensional transport channels, and when designing surface-sensitive measurements of Bi$_2$Se$_3$, ideally limiting air exposure to no more than a few minutes.
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- 2024
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6. Formation and Physical Properties of (NbTa)67336733(HfZr)67336733 Medium-Entropy Alloy and (NbTa)67336733(HfZrTi)67336733 High-Entropy Alloy Prepared by Mechanical Alloying
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Idczak, Rafał, Sobota, Piotr, Gnida, Daniel, Kołodziej, Sławomir, Chrząszcz, Beata, Pasturel, Mathieu, and Pikul, Adam
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- 2024
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7. Multi-Mode Front Lens for Momentum Microscopy: Part II Experiments
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Tkach, O., Fragkos, S., Nguyen, Q., Chernov, S., Scholz, M., Wind, N., Babenkov, S., Fedchenko, O., Lytvynenko, Y., Zimmer, D., Hloskovskii, A., Kutnyakhov, D., Pressacco, F., Dilling, J., Bruckmeier, L., Heber, M., Scholz, F., Sobota, J., Koralek, J., Sirica, N., Kallmayer, M., Hoesch, M., Schlueter, C., Odnodvorets, L. V., Mairesse, Y., Rossnagel, K., Elmers, H. -J., Beaulieu, S., and Schoenhense, G.
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Condensed Matter - Materials Science - Abstract
We have experimentally demonstrated different operating modes for the front lenses of the momentum microscopes described in Part I. Measurements at energies from vacuum UV at a high-harmonic generation (HHG)-based source to the soft and hard X-ray range at a synchrotron facility validated the results of theoretical ray-tracing calculations. The key element is a ring electrode concentric with the extractor electrode, which can tailor the field in the gap. First, the gap-lens-assisted extractor mode reduces the field strength at the sample while mitigating image aberrations. This mode gave good results in all spectral ranges. Secondly, by compensating the field at the sample surface with a negative voltage at the ring electrode we can operate in zero-field mode, which is beneficial for operando experiments. Finally, higher negative voltages establish the repeller mode, which removes all slow electrons below a certain kinetic energy to eliminate the primary contribution to the space-charge interaction in pump-probe experiments. The switch from extractor to repeller mode is associated with a reduction in the k-field-of-view (10-20 % at hard-X-ray energies, increasing to ~50% at low energies). Real-space imaging also benefits from the new lens modes as confirmed by ToF-XPEEM imaging with 650 nm resolution., Comment: 22 pages, 9 figures, 56 references
- Published
- 2024
8. Mail-Order Pharmacy Dispensing of Mifepristone for Medication Abortion After In-Person Screening
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Grossman, Daniel, Raifman, Sarah, Morris, Natalie, Arena, Andrea, Bachrach, Lela, Beaman, Jessica, Biggs, M Antonia, Collins, Amy, Hannum, Curtiss, Ho, Stephanie, Seibold-Simpson, Susan M, Sobota, Mindy, Tocce, Kristina, Schwarz, Eleanor B, and Gold, Marji
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Health Services and Systems ,Health Sciences ,Clinical Research ,Health Services ,Clinical Trials and Supportive Activities ,Good Health and Well Being ,Clinical Sciences ,Opthalmology and Optometry ,Public Health and Health Services ,Clinical sciences ,Health services and systems - Abstract
ImportanceBefore 2021, the US Food and Drug Administration required mifepristone to be dispensed in person, limiting access to medication abortion.ObjectiveTo estimate the effectiveness, acceptability, and feasibility of dispensing mifepristone for medication abortion using a mail-order pharmacy.Design, setting, and participantsThis prospective cohort study was conducted from January 2020 to May 2022 and included 11 clinics in 7 states (5 abortion clinics and 6 primary care sites, 4 of which were new to abortion provision). Eligible participants were seeking medication abortion at 63 or fewer days' gestation, spoke English or Spanish, were age 15 years or older, and were willing to take misoprostol buccally. After assessing eligibility for medication abortion through an in-person screening, mifepristone and misoprostol were prescribed using a mail-order pharmacy. Patients had standard follow-up care with the clinic. Clinical information was collected from medical records. Consenting participants completed online surveys about their experiences 3 and 14 days after enrolling. A total of 540 participants were enrolled; 10 withdrew or did not take medication. Data were analyzed from August 2022 to December 2023.InterventionMifepristone, 200 mg, and misoprostol, 800 µg, prescribed to a mail-order pharmacy and mailed to participants instead of dispensed in person.Main outcomes and measuresProportion of patients with a complete abortion with medications only, reporting satisfaction with the medication abortion, and reporting timely delivery of medications.ResultsClinical outcome information was obtained and analyzed for 510 abortions (96.2%) among 506 participants (median [IQR] age, 27 [23-31] years; 506 [100%] female; 194 [38.3%] Black, 88 [17.4%] Hispanic, 141 [27.9%] White, and 45 [8.9%] multiracial/other individuals). Of these, 436 participants (85.5%; 95% CI, 82.2%-88.4%) received medications within 3 days. Complete abortion occurred after medication use in 499 cases (97.8%; 95% CI, 96.2%-98.9%). There were 24 adverse events (4.7%) for which care was sought for medication abortion symptoms; 3 patients (0.6%; 95% CI, 0.1%-1.7%) experienced serious adverse events requiring hospitalization (1 with blood transfusion); however, no adverse events were associated with mail-order dispensing. Of 477 participants, 431 (90.4%; 95% CI, 87.3%-92.9%) indicated that they would use mail-order dispensing again for abortion care, and 435 participants (91.2%; 95% CI, 88.3%-93.6%) reported satisfaction with the medication abortion. Findings were similar to those of other published studies of medication abortion with in-person dispensing.Conclusions and relevanceThe findings of this cohort study indicate that mail-order pharmacy dispensing of mifepristone for medication abortion was effective, acceptable to patients, and feasible, with a low prevalence of serious adverse events. This care model should be expanded to improve access to medication abortion services.
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- 2024
9. Orbital Ingredients and Persistent Dirac Surface State for the Topological Band Structure in FeTe0.55Se0.45
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Li, Y-F, Chen, S-D, García-Díez, M, Iraola, MI, Pfau, H, Zhu, Y-L, Mao, Z-Q, Chen, T, Yi, M, Dai, P-C, Sobota, JA, Hashimoto, M, Vergniory, MG, Lu, D-H, and Shen, Z-X
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Physical Sciences ,Condensed Matter Physics ,Astronomical and Space Sciences ,Quantum Physics ,Physical sciences - Abstract
FeTe0.55Se0.45 (FTS) occupies a special spot in modern condensed matter physics at the intersections of electron correlation, topology, and unconventional superconductivity. The bulk electronic structure of FTS is predicted to be topologically nontrivial due to the band inversion between the dxz and pz bands along Γ-Z. However, there remain debates in both the authenticity of the Dirac surface states (DSSs) and the experimental deviations of band structure from the theoretical band inversion picture. Here we resolve these debates through a comprehensive angle-resolved photoemission spectroscopy investigation. We first observe a persistent DSS independent of kz. Then, by comparing FTS with FeSe, which has no band inversion along Γ-Z, we identify the spectral weight fingerprint of both the presence of the pz band and the inversion between the dxz and pz bands. Furthermore, we propose a renormalization scheme for the band structure under the framework of a tight-binding model preserving crystal symmetry. Our results highlight the significant influence of correlation on modifying the band structure and make a strong case for the existence of topological band structure in this unconventional superconductor.
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- 2024
10. Travel Medicine.
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Schwarz, Eleanor Bimla, Sobota, Mindy, and Treder, Kelly
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Biomedical and Clinical Sciences ,Clinical Sciences ,Humans ,Travel Medicine ,Travel ,Public Health and Health Services - Published
- 2024
11. Construction under Martin's axiom of a Boolean algebra with the Grothendieck property but without the Nikodym property
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Sobota, Damian and Zdomskyy, Lyubomyr
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Mathematics - Functional Analysis ,Mathematics - Logic - Abstract
Improving a result of M. Talagrand, under the assumption of a weak form of Martin's axiom, we construct a totally disconnected compact Hausdorff space $K$ such that the Banach space $C(K)$ of continuous real-valued functions on $K$ is a Grothendieck space but there exists a sequence $(\mu_n)$ of Radon measures on $K$ such that $\mu_n(A)\to0$ for every clopen set $A\subseteq K$ and $\int_Kfd\mu_n\not\to0$ for some $f\in C(K)$. Consequently, we get that Martin's axiom implies the existence of a Boolean algebra with the Grothendieck property but without the Nikodym property., Comment: New references added, minor corrections
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- 2023
12. Structural assessment of electric two-wheeler battery enclosure: thermal and structural study
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Chidambaram, Ramesh Kumar, Pedapati, Prithvi Raj, Kanna, P. Rajesh, Taler, Dawid, Sobota, Tomasz, and Taler, Jan
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- 2024
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13. Reversal of spin-polarization near the Fermi level of the Rashba semiconductor BiTeCl
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Qu, J, Han, X, Sakamoto, S, Jia, CJ, Liu, J, Li, H, Guan, D, Zeng, Y-J, Schüler, M, Kirchmann, PS, Moritz, B, Hussain, Z, Devereaux, TP, Shen, Z-X, and Sobota, JA
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Quantum Physics ,Physical Sciences ,Condensed Matter Physics ,Engineering ,Physical sciences - Abstract
Spin–orbit coupling forms the physical basis for quantum materials with non-trivial topology and potential spintronics applications. The Rashba interaction is a textbook model of spin–orbit interactions, with charge carriers undergoing linear, isotropic spin-splitting in momentum space. Recently, non-centrosymmetric semiconductors in the family BiTeX (X = Cl, Br, I) have been identified as exemplary Rashba materials due to the strong splitting of their bulk bands, yet a detailed investigation of their spin textures, and their relationships to local crystal symmetry, is currently lacking. We perform high-efficiency spin-resolved photoemission spectroscopy to directly image the spin texture of surface states of BiTeCl, and we find dramatic deviations from idealized behavior, including a reversal of the spin-polarization near the Fermi level. We show that this behavior can be described by higher-order contributions to the canonical Rashba model with the surface states localized to individual trilayers of the crystal. Due to the prominence of these effects near the Fermi level, they should have a strong impact on the spin-dependent transport of carriers.
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- 2023
14. TDP43 aggregation at ER-exit sites impairs ER-to-Golgi transport
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Hongyi Wu, Loo Chien Wang, Belle M. Sow, Damien Leow, Jin Zhu, Kathryn M. Gallo, Kathleen Wilsbach, Roshni Gupta, Lyle W. Ostrow, Crystal J. J. Yeo, Radoslaw M. Sobota, and Rong Li
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Science - Abstract
Abstract Protein aggregation plays key roles in age-related degenerative diseases, but how different proteins coalesce to form inclusions that vary in composition, morphology, molecular dynamics and confer physiological consequences is poorly understood. Here we employ a general reporter based on mutant Hsp104 to identify proteins forming aggregates in human cells under common proteotoxic stress. We identify over 300 proteins that form different inclusions containing subsets of aggregating proteins. In particular, TDP43, implicated in Amyotrophic Lateral Sclerosis (ALS), partitions dynamically between two distinct types of aggregates: stress granule and a previously unknown non-dynamic (solid-like) inclusion at the ER exit sites (ERES). TDP43-ERES co-aggregation is induced by diverse proteotoxic stresses and observed in the motor neurons of ALS patients. Such aggregation causes retention of secretory cargos at ERES and therefore delays ER-to-Golgi transport, providing a link between TDP43 aggregation and compromised cellular function in ALS patients.
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- 2024
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15. Synergistic effects of oxidative and acid stress on bacterial membranes of Escherichia coli and Staphylococcus simulans
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Min Xie, Eveline H. W. Koch, Cornelis A. van Walree, Ana Sobota, Andreas F. P. Sonnen, J. Antoinette Killian, Eefjan Breukink, and Joseph H. Lorent
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Biology (General) ,QH301-705.5 - Abstract
Abstract Oxidative stress in combination with acid stress has been shown to inactivate a wide spectrum of microorganisms, including multi-resistant bacteria. This occurs e.g. in phagolysosomes or during treatment by cold atmospheric pressure plasmas (CAP) and possibly depends on the cell membrane. We therefore explored the effects of CAP-generated reactive oxygen and nitrogen species (RONS) on bacterial growth inhibition and membranes in neutral and acidic suspensions. We observed that growth inhibition was most efficient when bacteria were treated by a mix of short and long-lived RONS in an acidic environment. Membrane packing was affected mainly upon contact with short-lived RONS, while also acidity strongly modulated packing. Under these conditions, Gram-negative bacteria displayed large potassium release while SYTOX Green influx remained marginal. Growth inhibition of Gram-negative bacteria correlated well with outer membrane (OM) permeabilization that occurred upon contact with short and/or long-lived RONS in synergy with acidity. In Gram-positive bacteria, CAP impaired membrane potential possibly through pore formation upon contact with short-lived RONS while formation of membrane protein hydroperoxides was probably involved in these effects. In summary, our study provides a wide perspective on understanding inactivation mechanisms of bacteria by RONS in combination with acidity.
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- 2024
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16. MONITORING OF THE IMPLEMENTATION OF THE EUROPEAN UNION'S SUSTAINABLE TRANSPORT DEVELOPMENT POLICY REGARDING THE USE OF LOW- AND ZERO-EMISSION FLEET ON THE EXAMPLE OF THE GÓRNOŚLĄSKA-ZAGŁĘBIOWSKA METROPOLIS (POLAND)
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Aleksander SOBOTA, Anna GRANÀ, Paulina ŚWIERK, and Elżbieta MACIOSZEK
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sustainable development ,urban transport ,emission standards ,low-emission transport ,zero-emission transport ,drive type ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Transportation engineering ,TA1001-1280 - Abstract
Nowadays, the majority of society decides to use individual transport for everyday travel, which negatively affects the congestion of cities. Nevertheless, in the transport policy of the European Union, public transport is becoming more and more important, which is reflected in strategic documents in the field of sustainable transport development. The effect of this action is to increase the attractiveness of public collective transport, which will also translate into a reduction in pollutant emissions. This article aims to verify the implementation of the European Union's sustainable transport development policy concerning the use of low- and zero-emission rolling stock in the Upper Silesian and Zagłębie Metropolis. As part of the work, the strategic documents of the European Union in the field of sustainable development of transport were analysed. In addition, the idea of establishing the Upper Silesian-Zagłębie Metropolis in the context of the policy of sustainable transport development was introduced and the public transport system functioning in the area of the Metropolis GZM was characterized.
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- 2024
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17. Keep an Eye on the Balance - The Influence of Experimental Training on Postural Stability in Ballet Dancers
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Artur Fredyk, Agata Bara, Anna Brachman, Grzegorz Sobota, and Bogdan Bacik
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One of the basic skills of a dancer is the ability to keep the body balance ("aplomb") while performing various dance figures. These movements are often performed with limited vision control due to dynamic motion or environmental conditions. Our aim was to verify whether the exercises with eyes closed of the ballet school students would reduce postural sway whilst improving the body balance. The training without visual feedback forces the body to rely more on information from the proprioceptive system about the alignment and motion of body parts in relation to each other and the external environment. In a group of thirteen female students of Comprehensive Ballet School, a significant reduction in postural sway was already found after three weeks of the nine-week training. This phenomenon occurred only during quiet standing with eyes closed. The use of stabilographic testing can be recommended as an objective evaluation of the "aplomb" level in ballet dancers. At the same time, this research showed that the introduction of ballet exercises with eyes closed improved postural stability without compromising stability with eyes open. Therefore, it can be assumed that such exercises do not harm but rather may be beneficial for the development of "aplomb."
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- 2024
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18. A high-resolution asymmetric von Hamos spectrometer for low-energy X-ray spectroscopy at the CRYRING@ESR electron cooler
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Jagodziński, P., Banaś, D., Pajek, M., Kubala-Kukuś, A., Jabłoński, Ł., Stabrawa, I., Szary, K., Sobota, D., Warczak, A., Gumberidze, A., Beyer, H. F., Lestinsky, M., Weber, G., Stöhlker, Th., and Trassinelli, M.
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Physics - Atomic Physics - Abstract
We present research program and project for high-resolution wavelength-dispersive spectrometer dedicated to low-energy X-ray spectroscopy at the electron cooler of the CRYRING@ESR storage ring, which is a part of the international Facility for Antiproton and Ion Research (FAIR) currently being built in Darmstadt. Due to the unique shape of the electorn-ion recombination X-ray source, resulting from the overlapping of the electron and ion beams in the electron cooler, the spectrometer can work in the specific asymmetric von Hamos (AvH) geometry. In order to completely eliminate the influence of Doppler effect on the measured X-ray energies, two asymmetric von Hamos spectrometers will be installed next to the dipole magnets on both sides of the electron cooler to detect blue/red (0$^{\circ}$/180$^{\circ}$) shifted X-rays, e.g. emitted in the radiative recombination (RR) process. The X-ray-tracing Monte-Carlo simulations show that the proposed AvH spectrometer will allow to determine with sub-meV precision, the low-energy X-rays (5-10 keV) emitted from stored bare or few-electron heavy ions interacting with cooling electrons. This experimental precision will enable accurate studies of the quantum electrodynamics (QED) effects in mid-Z H- and He-like ions.
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- 2023
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19. Ultrafast measurements of mode-specific deformation potentials of Bi$_2$Te$_3$ and Bi$_2$Se$_3$
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Huang, Yijing, Querales-Flores, José D., Teitelbaum, Samuel W., Cao, Jiang, Henighan, Thomas, Liu, Hanzhe, Jiang, Mason, De la Peña, Gilberto, Krapivin, Viktor, Haber, Johann, Sato, Takahiro, Chollet, Matthieu, Zhu, Diling, Katayama, Tetsuo, Power, Robert, Allen, Meabh, Rotundu, Costel R., Bailey, Trevor P., Uher, Ctirad, Trigo, Mariano, Kirchmann, Patrick S., Murray, Éamonn D., Shen, Zhi-Xun, Savic, Ivana, Fahy, Stephen, Sobota, Jonathan A., and Reis, David A.
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Condensed Matter - Materials Science - Abstract
Quantifying electron-phonon interactions for the surface states of topological materials can provide key insights into surface-state transport, topological superconductivity, and potentially how to manipulate the surface state using a structural degree of freedom. We perform time-resolved x-ray diffraction (XRD) and angle-resolved photoemission (ARPES) measurements on Bi$_2$Te$_3$ and Bi$_2$Se$_3$, following the excitation of coherent A$_{1g}$ optical phonons. We extract and compare the deformation potentials coupling the surface electronic states to local A$_{1g}$-like displacements in these two materials using the experimentally determined atomic displacements from XRD and electron band shifts from ARPES.We find the coupling in Bi$_2$Te$_3$ and Bi$_2$Se$_3$ to be similar and in general in agreement with expectations from density functional theory. We establish a methodology that quantifies the mode-specific electron-phonon coupling experimentally, allowing detailed comparison to theory. Our results shed light on fundamental processes in topological insulators involving electron-phonon coupling.
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- 2023
20. Spectroscopic evidence for topological band structure in FeTe$_{0.55}$Se$_{0.45}$
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Li, Y. -F., Chen, S. -D., Garcia-Diez, M., Iraola, M. I., Pfau, H., Zhu, Y. -L., Mao, Z. -Q., Chen, T., Yi, M., Dai, P. -C., Sobota, J. A., Hashimoto, M., Vergniory, M. G., Lu, D. -H., and Shen, Z. -X.
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Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Superconductivity - Abstract
FeTe$_{0.55}$Se$_{0.45}$(FTS) occupies a special spot in modern condensed matter physics at the intersections of electron correlation, topology, and unconventional superconductivity. The bulk electronic structure of FTS is predicted to be topologically nontrivial thanks to the band inversion between the $d_{xz}$ and $p_z$ bands along $\Gamma$-$Z$. However, there remain debates in both the authenticity of the Dirac surface states (DSS) and the experimental deviations of band structure from the theoretical band inversion picture. Here we resolve these debates through a comprehensive ARPES investigation. We first observe a persistent DSS independent of $k_z$. Then, by comparing FTS with FeSe which has no band inversion along $\Gamma$-$Z$, we identify the spectral weight fingerprint of both the presence of the $p_z$ band and the inversion between the $d_{xz}$ and $p_z$ bands. Furthermore, we propose a reconciling band structure under the framework of a tight-binding model preserving crystal symmetry. Our results highlight the significant influence of correlation on modifying the band structure and make a strong case for the existence of topological band structure in this unconventional superconductor.
- Published
- 2023
21. TDP43 aggregation at ER-exit sites impairs ER-to-Golgi transport
- Author
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Wu, Hongyi, Wang, Loo Chien, Sow, Belle M., Leow, Damien, Zhu, Jin, Gallo, Kathryn M., Wilsbach, Kathleen, Gupta, Roshni, Ostrow, Lyle W., Yeo, Crystal J. J., Sobota, Radoslaw M., and Li, Rong
- Published
- 2024
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22. Synergistic effects of oxidative and acid stress on bacterial membranes of Escherichia coli and Staphylococcus simulans
- Author
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Xie, Min, Koch, Eveline H. W., Walree, Cornelis A. van, Sobota, Ana, Sonnen, Andreas F. P., Killian, J. Antoinette, Breukink, Eefjan, and Lorent, Joseph H.
- Published
- 2024
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23. Electrical properties determine the liquid flow direction in plasma–liquid interactions
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Ryan, Calum T., Darhuber, Anton A., Kunnen, Rudie P. J., Gelderblom, Hanneke, and Sobota, Ana
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- 2024
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24. Ultra-high throughput-based screening for the discovery of antiplatelet drugs affecting receptor dependent calcium signaling dynamics
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Fernández, Delia I., Troitiño, Sara, Sobota, Vladimír, Tullemans, Bibian M. E., Zou, Jinmi, van den Hurk, Helma, García, Ángel, Honarnejad, Saman, Kuijpers, Marijke J. E., and Heemskerk, Johan W. M.
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- 2024
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25. The Josefson–Nissenzweig theorem and filters on ω
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Marciszewski, Witold and Sobota, Damian
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- 2024
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26. On sequences of finitely supported measures related to the Josefson--Nissenzweig theorem
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Marciszewski, Witold, Sobota, Damian, and Zdomskyy, Lyubomyr
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Mathematics - General Topology ,Mathematics - Functional Analysis - Abstract
Given a Tychonoff space $X$, we call a sequence $\langle\mu_n\colon n\in\omega\rangle$ of signed Borel measures on $X$ a finitely supported Josefson--Nissenzweig sequence (in short a JN-sequence) if: 1) for every $n\in\omega$ the measure $\mu_n$ is a finite combination of one-point measures and $\|\mu_n\|=1$, and 2) $\int_Xf\,\mathrm{d}\mu_n\to0$ for every continuous function $f\in C(X)$. Our main result asserts that if a Tychonoff space $X$ admits a JN-sequence, then there exists a JN-sequence $\langle\mu_n\colon n\in\omega\rangle$ such that: i) $\mbox{supp}(\mu_n)\cap\mbox{supp}(\mu_k)=\emptyset$ for every $n\neq k\in\omega$, and ii) the union $\bigcup_{n\in\omega}\mbox{supp}(\mu_n)$ is a discrete subset of $X$. We also prove that if a Tychonoff space $X$ carries a JN-sequence, then either there is a JN-sequence $\langle\mu_n\colon n\in\omega\rangle$ on $X$ such that $|\mbox{supp}(\mu_n)|=2$ for every $n\in\omega$, or for every JN-sequence $\langle\mu_n\colon n\in\omega\rangle$ on $X$ we have $\lim_{n\to\infty}|\mbox{supp}(\mu_n)|=\infty$., Comment: arXiv admin note: substantial text overlap with arXiv:2009.07552
- Published
- 2023
27. Author Correction: METTL8 links mt-tRNA m3C modification to the HIF1α/RTK/Akt axis to sustain GBM stemness and tumorigenicity
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Bernice Woon Li Lee, You Heng Chuah, Jeehyun Yoon, Oleg V. Grinchuk, Yajing Liang, Jayshree L. Hirpara, Yating Shen, Loo Chien Wang, Yan Ting Lim, Tianyun Zhao, Radoslaw M. Sobota, Tseng Tsai Yeo, Andrea Li Ann Wong, Kejia Teo, Vincent Diong Weng Nga, Bryce Wei Quan Tan, Toshio Suda, Tan Boon Toh, Shazib Pervaiz, Zhewang Lin, and Derrick Sek Tong Ong
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Cytology ,QH573-671 - Published
- 2024
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28. Electrical properties determine the liquid flow direction in plasma–liquid interactions
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Calum T. Ryan, Anton A. Darhuber, Rudie P. J. Kunnen, Hanneke Gelderblom, and Ana Sobota
- Subjects
Medicine ,Science - Abstract
Abstract During atmospheric pressure plasma impingement, plasma induced liquid flow will influence the transport and distribution of plasma generated charged and reactive species in liquids. We use particle image velocimetry and supplementary pH, conductivity and temperature measurements to investigate electrical properties of an AC kHz plasma jet interacting with water and electrolytes. We observe that the dominant driving mechanism in low conductive solutions are surface forces such as shear stresses and stagnation-pressure induced dimpling. These give upwards flows beneath the plasma–liquid interaction point. In highly conductive solutions, such as water with dissolved salts, the dominant driving mechanism is electro-hydrodynamic forces, with flows directed downwards underneath the plasma jet in our system. We therefore demonstrate that the direction of initial plasma induced liquid flows can be controlled through the addition of salt ions. In electrically grounded salt solutions, we also observe time resolved flow direction switching, possibly due to modification of salt solutions via electrolytic and plasma induced reactions changing the dominant flow mechanism over time.
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- 2024
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29. Are e-cigarettes really a healthier alternative to smoking?
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Michał Zwoliński, Katarzyna Zemsta, Marta Szuleka, Weronika Sobota, Katarzyna Kamińska-Omasta, Przemysław Piskorz, Bartłomiej Kulesza, and Ryszard Tomasiuk
- Subjects
vaping ,electronic nicotine delivery systems ,oxidative stress ,carcinogenesis. ,Medicine - Abstract
E-cigarettes emerged in the early 21st century as a safer health alternative to conventional cigarettes. E-cigarettes use e-liquids based on glycerine and propylene glycol. This results in smaller amounts of toxic substances in the aerosol they produce compared to traditional cigarettes. The rather short existence of such replacements does not make it clear whether they are actually better for smokers’ health. The increasing number and younger age of smokers has prompted researchers to expand their research on the subject. A review of literature has shown that e-cigarettes affect many biochemical mechanisms, affecting the health of their users. They cause oxidative stress and, consequently, a cytotoxic effect; an increase in the production of mucins, taking part in lung diseases; affect the formation of DNA damage, carcinogenesis, sensitivity to chemotherapy, inflammatory response and disrupt cytokine levels in tissues. In addition, they cause thinning of the laryngeal mucosa, autophagy of middle ear epithelial cells, apoptosis of gingival fibroblasts, weakening of the tooth attachment apparatus and promote dental caries. It will take some time to test the theory of whether e-cigarettes are a healthier substitute for classic cigarettes, but based on current knowledge, one should be aware that these substances can cause adverse health effects.
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- 2024
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30. Author Correction: METTL8 links mt-tRNA m3C modification to the HIF1α/RTK/Akt axis to sustain GBM stemness and tumorigenicity
- Author
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Lee, Bernice Woon Li, Chuah, You Heng, Yoon, Jeehyun, Grinchuk, Oleg V., Liang, Yajing, Hirpara, Jayshree L., Shen, Yating, Wang, Loo Chien, Lim, Yan Ting, Zhao, Tianyun, Sobota, Radoslaw M., Yeo, Tseng Tsai, Wong, Andrea Li Ann, Teo, Kejia, Nga, Vincent Diong Weng, Tan, Bryce Wei Quan, Suda, Toshio, Toh, Tan Boon, Pervaiz, Shazib, Lin, Zhewang, and Ong, Derrick Sek Tong
- Published
- 2024
- Full Text
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31. An anti-LpqH human monoclonal antibody from an asymptomatic individual mediates protection against Mycobacterium tuberculosis.
- Author
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Krishnananthasivam, Shivankari, Li, Hao, Bouzeyen, Rania, Shunmuganathan, Bhuvaneshwari, Purushotorman, Kiren, Liao, Xinlei, Du, Fengjiao, Friis, Claudia, Crawshay-Williams, Felicity, Boon, Low, Xinlei, Qian, Chan, Conrad, Sobota, Radoslaw, Kozma, Mary, Jo, Valeria, Wang, Guirong, Huang, Hairong, Floto, Andreas, Bifani, Pablo, MacAry, Paul, and Javid, Babak
- Abstract
Tuberculosis (TB) is an airborne disease caused by Mycobacterium tuberculosis (Mtb). Whilst a functional role for humoral immunity in Mtb protection remains poorly defined, previous studies have suggested that antibodies can contribute towards host defense. Thus, identifying the critical components in the antibody repertoires from immune, chronically exposed, healthy individuals represents an approach for identifying new determinants for natural protection. In this study, we performed a thorough analysis of the IgG/IgA memory B cell repertoire from occupationally exposed, immune volunteers. We detail the identification and selection of a human monoclonal antibody that exhibits protective activity in vivo and show that it targets a virulence factor LpqH. Intriguingly, protection in both human ex vivo and murine challenge experiments was isotype dependent, with most robust protection being mediated via IgG2 and IgA. These data have important implications for our understanding of natural mucosal immunity for Mtb and highlight a new target for future vaccine development.
- Published
- 2023
32. WNTinib is a multi-kinase inhibitor with specificity against β-catenin mutant hepatocellular carcinoma
- Author
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Rialdi, Alex, Duffy, Mary, Scopton, Alex P, Fonseca, Frank, Zhao, Julia Nanyi, Schwarz, Megan, Molina-Sanchez, Pedro, Mzoughi, Slim, Arceci, Elisa, Abril-Fornaguera, Jordi, Meadows, Austin, Ruiz de Galarreta, Marina, Torre, Denis, Reyes, Kyna, Lim, Yan Ting, Rosemann, Felix, Khan, Zaigham M, Mohammed, Kevin, Wang, Xuedi, Yu, Xufen, Lakshmanan, Manikandan, Rajarethinam, Ravisankar, Tan, Soo Yong, Jin, Jian, Villanueva, Augusto, Michailidis, Eleftherios, De Jong, Ype P, Rice, Charles M, Marazzi, Ivan, Hasson, Dan, Llovet, Josep M, Sobota, Radoslaw M, Lujambio, Amaia, Guccione, Ernesto, and Dar, Arvin C
- Subjects
Biomedical and Clinical Sciences ,Oncology and Carcinogenesis ,Digestive Diseases ,Rare Diseases ,Liver Disease ,Biotechnology ,Liver Cancer ,Genetics ,Cancer ,Development of treatments and therapeutic interventions ,5.1 Pharmaceuticals ,Good Health and Well Being ,Humans ,Mice ,Animals ,Carcinoma ,Hepatocellular ,beta Catenin ,Liver Neoplasms ,Transcription Factors ,Antineoplastic Agents ,Protein Kinase Inhibitors ,Immunology ,Oncology and carcinogenesis - Abstract
Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths worldwide. β-Catenin (CTNNB1)-mutated HCC represents 30% of cases of the disease with no precision therapeutics available. Using chemical libraries derived from clinical multi-kinase inhibitor (KI) scaffolds, we screened HCC organoids to identify WNTinib, a KI with exquisite selectivity in CTNNB1-mutated human and murine models, including patient samples. Multiomic and target engagement analyses, combined with rescue experiments and in vitro and in vivo efficacy studies, revealed that WNTinib is superior to clinical KIs and inhibits KIT/mitogen-activated protein kinase (MAPK) signaling at multiple nodes. Moreover, we demonstrate that reduced engagement on BRAF and p38α kinases by WNTinib relative to several multi-KIs is necessary to avoid compensatory feedback signaling-providing a durable and selective transcriptional repression of mutant β-catenin/Wnt targets through nuclear translocation of the EZH2 transcriptional repressor. Our studies uncover a previously unknown mechanism to harness the KIT/MAPK/EZH2 pathway to potently and selectively antagonize CTNNB1-mutant HCC with an unprecedented wide therapeutic index.
- Published
- 2023
33. Credentialing Internal Medicine Physicians to Expand Long-Acting Reversible Contraceptive Access.
- Author
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Michener, Jennifer L, Hirsh, David A, Batur, Pelin, Casas, Rachel S, Gopinath, Vidya, Pace, Lydia E, Prifti, Christine, Rusiecki, Jennifer, Schwarz, Eleanor Bimla, Shankar, Megha, Sobota, Mindy, and Gomez Kwolek, Deborah
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Biomedical and Clinical Sciences ,Clinical Sciences ,Public Health and Health Services - Published
- 2023
34. Energy deposition and formation of nanostructures in the interaction of highly charged xenon ions with gold nanolayers
- Author
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Stabrawa, I., Banaś, D., Kubala-Kukuś, A., Jabłoński, Ł., Jagodziński, Sobota, D., Szary, K., Pajek, M., Skrzypiec, K., Mendyk, E., Borysiewicz, M., Majkić, M. D., and Nedeljković, N. N.
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Physics - Atomic Physics ,Condensed Matter - Materials Science ,Physics - Applied Physics - Abstract
The effect of the deposition of kinetic energy and neutralization energy of slow highly charged xenon ions on the process of the nanostructures creation at the surface of gold nanolayers is investigated. The nanolayers of thickness of 100 nm were prepared by e-beam evaporation of gold on crystalline silicon Si(100) substrate. The samples were irradiated at the Kielce EBIS facility of the Jan Kochanowski University (Kielce, Poland), under high vacuum conditions. The irradiations were performed for constant kinetic energy 280 keV and different ions charge states (Xe$^{q+}$, q = 25, 30, 35, 36 and 40) and for constant charge state Xe$^{35+}$ and different kinetic energies: 280 keV, 360 keV, 420 keV and 480 keV. The fluence of the ions was on the level of 10$^{10}$ ions/cm$^2$. Before and after irradiation the nanolayer surfaces were investigated using the atomic force microscope. As the result, well pronounced modifications of the nanolayer surfaces in the form of craters have been observed. A systematic analysis of the crater sizes (diameter on the surface and depth) allowed us to determine the influence of the deposited kinetic and the neutralization energy on the size of the obtained nanostructures. The results are theoretically interpreted within the micro-staircase model based on the quantum two-state vector model of the ionic Rydberg states population. The charge dependent ion-atom interaction potential inside the solid is used for the calculation of the nuclear stopping power. According to the model the formation of the nanostructures is governed by the processes of the ionic neutralization in front of the surface and the kinetic energy loss inside the solid., Comment: 12 pages, 7 figures, Submitted to Vacuum journal on May 29th, 2022
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- 2023
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35. Influence of local symmetry on lattice dynamics coupled to topological surface states
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Sobota, Jonathan A., Teitelbaum, Samuel W., Huang, Yijing, Querales-Flores, José D., Power, Robert, Allen, Meabh, Rotundu, Costel R., Bailey, Trevor P., Uher, Ctirad, Henighan, Tom, Jiang, Mason, Zhu, Diling, Chollet, Matthieu, Sato, Takahiro, Trigo, Mariano, Murray, Éamonn D., Savić, Ivana, Kirchmann, Patrick S., Fahy, Stephen, Reis, David. A., and Shen, Zhi-Xun
- Subjects
Condensed Matter - Materials Science - Abstract
We investigate coupled electron-lattice dynamics in the topological insulator Bi2Te3 with time-resolved photoemission and time-resolved x-ray diffraction. It is well established that coherent phonons can be launched by optical excitation, but selection rules generally restrict these modes to zone-center wavevectors and Raman-active branches. We find that the topological surface state couples to additional modes, including a continuum of surface-projected bulk modes from both Raman- and infrared-branches, with possible contributions from surface-localized modes when they exist. Our calculations show that this surface vibrational spectrum occurs naturally as a consequence of the translational and inversion symmetries broken at the surface, without requiring the splitting-off of surface-localized phonon modes. The generality of this result suggests that coherent phonon spectra are useful by providing unique fingerprints for identifying surface states in more controversial materials. These effects may also expand the phase space for tailoring surface state wavefunctions via ultrafast optical excitation.
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- 2022
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36. Ashwagandha and stress
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Weronika Sobota, Przemysław Piskorz, Katarzyna Zemsta, Michał Zwoliński, Mateusz Tyniec, and Kamal Morshed
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ashwagandha ,stress ,Education ,Sports ,GV557-1198.995 ,Medicine - Abstract
Ashwagandha, also known as Withania somnifera, is an adaptogen gaining popularity as a natural stress reducer. Stress is a common phenomenon caused by factors such as lifestyle, work pressure or social conflict, and has a negative impact on both mental and physical health. In response to these challenges, more and more people are looking for natural solutions, and adaptogens such as ashwagandha offer support in dealing with stress without significant side effects. Scientific research shows that ashwagandha can lower levels of the stress hormone cortisol and improve results on tests assessing stress, anxiety and depression. Numerous studies conducted on both animals and humans confirm its beneficial effects on mental and physical health, including improvement of cognitive functions, sleep quality and emotional well-being. The mechanism of action of ashwagandha includes regulation of the HPA axis, reduction of glucocorticoids and modulation of the immune system. Despite promising results, further research is needed to fully understand its mechanism of action, assess long-term effects, and investigate possible interactions with other drugs. Ashwagandha seems to be a safe and effective agent in the fight against stress, but it is recommended to consult a doctor before starting supplementation.
- Published
- 2024
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37. Application of irreversible electroporation ablation in oncology - a narrative review
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Dawid Piecuch, Edyta Hańczyk, Weronika Sobota, and Przemysław Piskorz
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Irreversible electroporation-IRE ,literature review ,prostate cancer (PCa) ,Perihinal bile tract cancer ,Pancreatic cancer ,Kidney tumors ,Sports ,GV557-1198.995 ,Sports medicine ,RC1200-1245 - Abstract
Irreversible electroporation-IRE is an innovative cancer treatment method that can selectively destroy cancer cells without damaging surrounding tissues. It is a safe and effective alternative to traditional methods, with the patient faster recover potential and spare critical body structures such as blood vessels and nerves.In surgical oncology, the IRE treatment technique is used especially in cases where other methods are not possible or have limited effectiveness. The method is proving to be seen as an effective local treatment with good clinical results and limited side effects in prostate, biliary, pancreatic, kidney and liver cancers.
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- 2024
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38. New Route to Synthesize High-Entropy Carbide Powders by Mechanical Alloying
- Author
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Idczak, Rafał, Sobota, Piotr, Tran, Lan Maria, Babij, Michał, Idczak, Karolina, Nowak, Wojciech, and Pikul, Adam
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- 2024
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39. Convergence of measures after adding a real
- Author
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Sobota, Damian and Zdomskyy, Lyubomyr
- Published
- 2024
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40. Motor Signature Differences Between Autism Spectrum Disorder and Developmental Coordination Disorder, and Their Neural Mechanisms
- Author
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Butera, Christiana, Delafield-Butt, Jonathan, Lu, Szu-Ching, Sobota, Krzysztof, McGowan, Timothy, Harrison, Laura, Kilroy, Emily, Jayashankar, Aditya, and Aziz-Zadeh, Lisa
- Published
- 2023
- Full Text
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41. METTL8 links mt-tRNA m3C modification to the HIF1α/RTK/Akt axis to sustain GBM stemness and tumorigenicity
- Author
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Bernice Woon Li Lee, You Heng Chuah, Jeehyun Yoon, Oleg V. Grinchuk, Yajing Liang, Jayshree L. Hirpara, Yating Shen, Loo Chien Wang, Yan Ting Lim, Tianyun Zhao, Radoslaw M. Sobota, Tseng Tsai Yeo, Andrea Li Ann Wong, Kejia Teo, Vincent Diong Weng Nga, Bryce Wei Quan Tan, Toshio Suda, Tan Boon Toh, Shazib Pervaiz, Zhewang Lin, and Derrick Sek Tong Ong
- Subjects
Cytology ,QH573-671 - Abstract
Abstract Epitranscriptomic RNA modifications are crucial for the maintenance of glioma stem cells (GSCs), the most malignant cells in glioblastoma (GBM). 3-methylcytosine (m3C) is a new epitranscriptomic mark on RNAs and METTL8 represents an m3C writer that is dysregulated in cancer. Although METTL8 has an established function in mitochondrial tRNA (mt-tRNA) m3C modification, alternative splicing of METTL8 can also generate isoforms that localize to the nucleolus where they may regulate R-loop formation. The molecular basis for METTL8 dysregulation in GBM, and which METTL8 isoform(s) may influence GBM cell fate and malignancy remain elusive. Here, we investigated the role of METTL8 in regulating GBM stemness and tumorigenicity. In GSC, METTL8 is exclusively localized to the mitochondrial matrix where it installs m3C on mt-tRNAThr/Ser(UCN) for mitochondrial translation and respiration. High expression of METTL8 in GBM is attributed to histone variant H2AZ-mediated chromatin accessibility of HIF1α and portends inferior glioma patient outcome. METTL8 depletion impairs the ability of GSC to self-renew and differentiate, thus retarding tumor growth in an intracranial GBM xenograft model. Interestingly, METTL8 depletion decreases protein levels of HIF1α, which serves as a transcription factor for several receptor tyrosine kinase (RTK) genes, in GSC. Accordingly, METTL8 loss inactivates the RTK/Akt axis leading to heightened sensitivity to Akt inhibitor treatment. These mechanistic findings, along with the intimate link between METTL8 levels and the HIF1α/RTK/Akt axis in glioma patients, guided us to propose a HIF1α/Akt inhibitor combination which potently compromises GSC proliferation/self-renewal in vitro. Thus, METTL8 represents a new GBM dependency that is therapeutically targetable.
- Published
- 2024
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42. Ultra-high throughput-based screening for the discovery of antiplatelet drugs affecting receptor dependent calcium signaling dynamics
- Author
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Delia I. Fernández, Sara Troitiño, Vladimír Sobota, Bibian M. E. Tullemans, Jinmi Zou, Helma van den Hurk, Ángel García, Saman Honarnejad, Marijke J. E. Kuijpers, and Johan W. M. Heemskerk
- Subjects
Collagen ,Cytosolic calcium ,Glycoprotein VI ,Prestwick library ,Thrombin ,Thrombosis ,Medicine ,Science - Abstract
Abstract Distinct platelet activation patterns are elicited by the tyrosine kinase-linked collagen receptor glycoprotein VI (GPVI) and the G-protein coupled protease-activated receptors (PAR1/4) for thrombin. This is reflected in the different platelet Ca2+ responses induced by the GPVI agonist collagen-related peptide (CRP) and the PAR1/4 agonist thrombin. Using a 96 well-plate assay with human Calcium-6-loaded platelets and a panel of 22 pharmacological inhibitors, we assessed the cytosolic Ca2+ signaling domains of these receptors and developed an automated Ca2+ curve algorithm. The algorithm was used to evaluate an ultra-high throughput (UHT) based screening of 16,635 chemically diverse small molecules with orally active physicochemical properties for effects on platelets stimulated with CRP or thrombin. Stringent agonist-specific selection criteria resulted in the identification of 151 drug-like molecules, of which three hit compounds were further characterized. The dibenzyl formamide derivative ANO61 selectively modulated thrombin-induced Ca2+ responses, whereas the aromatic sulfonyl imidazole AF299 and the phenothiazine ethopropazine affected CRP-induced responses. Platelet functional assays confirmed selectivity of these hits. Ethopropazine retained its inhibitory potential in the presence of plasma, and suppressed collagen-dependent thrombus buildup at arterial shear rate. In conclusion, targeting of platelet Ca2+ signaling dynamics in a screening campaign has the potential of identifying novel platelet-inhibiting molecules.
- Published
- 2024
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43. Grothendieck $C(K)$-spaces and the Josefson--Nissenzweig theorem
- Author
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Kąkol, Jerzy, Sobota, Damian, and Zdomskyy, Lyubomyr
- Subjects
Mathematics - Functional Analysis ,Mathematics - General Topology - Abstract
For a compact space $K$, the Banach space $C(K)$ is said to have the $\ell_1$-Grothendieck property if every weak* convergent sequence $\big\langle\mu_n\colon\ n\in\omega\big\rangle$ of functionals on $C(K)$ such that $\mu_n\in\ell_1(K)$ for every $n\in\omega$, is weakly convergent. Thus, the $\ell_1$-Grothendieck property is a weakening of the standard Grothendieck property for Banach spaces of continuous functions. We observe that $C(K)$ has the $\ell_1$-Grothendieck property if and only if there does not exist any sequence of functionals $\big\langle\mu_n\colon\ n\in\omega\big\rangle$ on $C(K)$, with $\mu_n\in\ell_1(K)$ for every $n\in\omega$, satisfying the conclusion of the classical Josefson--Nissenzweig theorem. We construct an example of a separable compact space $K$ such that $C(K)$ has the $\ell_1$-Grothendieck property but it does not have the Grothendieck property. We also show that for many classical consistent examples of Efimov spaces $K$ their Banach spaces $C(K)$ do not have the $\ell_1$-Grothendieck property., Comment: arXiv admin note: substantial text overlap with arXiv:2009.07552
- Published
- 2022
44. On complementability of $c_0$ in spaces $C(K\times L)$
- Author
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Kąkol, Jerzy, Sobota, Damian, and Zdomskyy, Lyubomyr
- Subjects
Mathematics - Functional Analysis ,Mathematics - General Topology ,Mathematics - Probability - Abstract
Using elementary probabilistic methods, in particular a variant of the Weak Law of Large Numbers related to the Bernoulli distribution, we prove that for every infinite compact spaces $K$ and $L$ the product $K\times L$ admits a sequence $\langle\mu_n\colon n\in\mathbb{N}\rangle$ of normalized signed measures with finite supports which converges to $0$ with respect to the weak* topology of the dual Banach space $C(K\times L)^*$. Our approach is completely constructive -- the measures $\mu_n$ are defined by an explicit simple formula. We also show that this result generalizes the classical theorem of Cembranos and Freniche which states that for every infinite compact spaces $K$ and $L$ the Banach space $C(K\times L)$ contains a complemented copy of the space $c_0$., Comment: 7 pages, 1 open problem! arXiv admin note: text overlap with arXiv:2009.07552
- Published
- 2022
45. Coherent Light Control of a Metastable Hidden Phase
- Author
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Maklar, J., Dong, S., Sarkar, J., Gerasimenko, Y. A., Pincelli, T., Beaulieu, S., Kirchmann, P. S., Sobota, J. A., Yang, S. -L., Leuenberger, D., Moore, R. G., Shen, Z. -X., Wolf, M., Mihailovic, D., Ernstorfer, R., and Rettig, L.
- Subjects
Condensed Matter - Materials Science - Abstract
Metastable phases present a promising route to expand the functionality of complex materials. Of particular interest are light-induced metastable phases that are inaccessible under equilibrium conditions, as they often host new, emergent properties switchable on ultrafast timescales. However, the processes governing the trajectories to such hidden phases remain largely unexplored. Here, using time- and angle-resolved photoemission spectroscopy, we investigate the ultrafast dynamics of the formation of a hidden quantum state in the layered dichalcogenide 1T-TaS$_2$ upon photoexcitation. Our results reveal the nonthermal character of the transition governed by a collective charge-density-wave excitation. Utilizing a double-pulse excitation of the structural mode, we show vibrational coherent control of the phase-transition efficiency. Our demonstration of exceptional control, switching speed, and stability of the hidden phase are key for device applications., Comment: 17 pages, 13 figures
- Published
- 2022
46. Signatures of the exciton gas phase and its condensation in monolayer 1T-ZrTe2
- Author
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Song, Yekai, Jia, Chunjing, Xiong, Hongyu, Wang, Binbin, Jiang, Zhicheng, Huang, Kui, Hwang, Jinwoong, Li, Zhuojun, Hwang, Choongyu, Liu, Zhongkai, Shen, Dawei, Sobota, Jonathan A, Kirchmann, Patrick, Xue, Jiamin, Devereaux, Thomas P, Mo, Sung-Kwan, Shen, Zhi-Xun, and Tang, Shujie
- Subjects
Quantum Physics ,Physical Sciences ,Condensed Matter Physics - Abstract
The excitonic insulator (EI) is a Bose-Einstein condensation (BEC) of excitons bound by electron-hole interaction in a solid, which could support high-temperature BEC transition. The material realization of EI has been challenged by the difficulty of distinguishing it from a conventional charge density wave (CDW) state. In the BEC limit, the preformed exciton gas phase is a hallmark to distinguish EI from conventional CDW, yet direct experimental evidence has been lacking. Here we report a distinct correlated phase beyond the 2×2 CDW ground state emerging in monolayer 1T-ZrTe2 and its investigation by angle-resolved photoemission spectroscopy (ARPES) and scanning tunneling microscopy (STM). The results show novel band- and energy-dependent folding behavior in a two-step process, which is the signatures of an exciton gas phase prior to its condensation into the final CDW state. Our findings provide a versatile two-dimensional platform that allows tuning of the excitonic effect.
- Published
- 2023
47. METTL8 links mt-tRNA m3C modification to the HIF1α/RTK/Akt axis to sustain GBM stemness and tumorigenicity
- Author
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Lee, Bernice Woon Li, Chuah, You Heng, Yoon, Jeehyun, Grinchuk, Oleg V., Liang, Yajing, Hirpara, Jayshree L., Shen, Yating, Wang, Loo Chien, Lim, Yan Ting, Zhao, Tianyun, Sobota, Radoslaw M., Yeo, Tseng Tsai, Wong, Andrea Li Ann, Teo, Kejia, Nga, Vincent Diong Weng, Tan, Bryce Wei Quan, Suda, Toshio, Toh, Tan Boon, Pervaiz, Shazib, Lin, Zhewang, and Ong, Derrick Sek Tong
- Published
- 2024
- Full Text
- View/download PDF
48. P025Mail-order pharmacy dispensing of mifepristone for medication abortion after in-person clinical assessment
- Author
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Grossman, D, Raifman, S, Morris, N, Biggs, MA, Arena, A, Bachrach, L, Beaman, J, Collins, A, Gold, M, Hannum, C, Ho, S, Middleton, T, Schwarz, EB, Tocce, K, Seibold-Simpson, S, Sobota, M, and Wohler, D
- Subjects
Reproductive Medicine ,Biomedical and Clinical Sciences ,Clinical Research ,Reproductive health and childbirth ,Clinical Sciences ,Paediatrics and Reproductive Medicine ,Public Health and Health Services ,Obstetrics & Reproductive Medicine ,Clinical sciences ,Reproductive medicine ,Health services and systems - Published
- 2022
49. Multi-omic analysis of bat versus human fibroblasts reveals altered central metabolism
- Author
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N Suhas Jagannathan, Javier Yu Peng Koh, Younghwan Lee, Radoslaw Mikolaj Sobota, Aaron T Irving, Lin-fa Wang, Yoko Itahana, Koji Itahana, and Lisa Tucker-Kellogg
- Subjects
bat metabolism ,ferroptosis ,ischemia ,flux modeling ,succinate accumulation ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Bats have unique characteristics compared to other mammals, including increased longevity and higher resistance to cancer and infectious disease. While previous studies have analyzed the metabolic requirements for flight, it is still unclear how bat metabolism supports these unique features, and no study has integrated metabolomics, transcriptomics, and proteomics to characterize bat metabolism. In this work, we performed a multi-omics data analysis using a computational model of metabolic fluxes to identify fundamental differences in central metabolism between primary lung fibroblast cell lines from the black flying fox fruit bat (Pteropus alecto) and human. Bat cells showed higher expression levels of Complex I components of electron transport chain (ETC), but, remarkably, a lower rate of oxygen consumption. Computational modeling interpreted these results as indicating that Complex II activity may be low or reversed, similar to an ischemic state. An ischemic-like state of bats was also supported by decreased levels of central metabolites and increased ratios of succinate to fumarate in bat cells. Ischemic states tend to produce reactive oxygen species (ROS), which would be incompatible with the longevity of bats. However, bat cells had higher antioxidant reservoirs (higher total glutathione and higher ratio of NADPH to NADP) despite higher mitochondrial ROS levels. In addition, bat cells were more resistant to glucose deprivation and had increased resistance to ferroptosis, one of the characteristics of which is oxidative stress. Thus, our studies revealed distinct differences in the ETC regulation and metabolic stress responses between human and bat cells.
- Published
- 2024
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- View/download PDF
50. Analysis of drug-induced and spontaneous cardioversions reveals similar patterns leading to termination of atrial fibrillation
- Author
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Arne van Hunnik, Vladimír Sobota, Stef Zeemering, Dragan Opacic, Billy Scaf, Elisa D’Alessandro, Karel Oyaert, Marion Kuiper, Jonas G. Diness, Ulrik S. Sørensen, James T. Milnes, Marcel A. G. van der Heyden, Thomas Jespersen, Ulrich Schotten, and Sander Verheule
- Subjects
antiarrhythmic drugs ,atrial anatomy ,atrial fibrillation ,Bachmann’s bundle ,cardioversion ,Physiology ,QP1-981 - Abstract
IntroductionThe mechanisms leading to the conversion of atrial fibrillation (AF) to sinus rhythm are poorly understood. This study describes the dynamic behavior of electrophysiological parameters and conduction patterns leading to spontaneous and pharmacological AF termination.MethodsFive independent groups of goats were investigated: (1) spontaneous termination of AF, and drug-induced terminations of AF by various potassium channel inhibitors: (2) AP14145, (3) PA-6, (4) XAF-1407, and (5) vernakalant. Bi-atrial contact mapping was performed during an open chest surgery and intervals with continuous and discrete atrial activity were determined. AF cycle length (AFCL), conduction velocity and path length were calculated for each interval, and the final conduction pattern preceding AF termination was evaluated.ResultsAF termination was preceded by a sudden episode of discrete activity both in the presence and absence of an antiarrhythmic drug. This episode was accompanied by substantial increases in AFCL and conduction velocity, resulting in prolongation of path length. In 77% ± 4% of all terminations the conduction pattern preceding AF termination involved medial to lateral conduction along Bachmann’s bundle into both atria, followed by anterior to posterior conduction. This finding suggests conduction block in the interatrial septum and/or pulmonary vein area as final step of AF termination.ConclusionAF termination is preceded by an increased organization of fibrillatory conduction. The termination itself is a sudden process with a critical role for the interplay between spatiotemporal organization and anatomical structure.
- Published
- 2024
- Full Text
- View/download PDF
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