Abstract
We present a systematic analysis of type C quasiperiodic oscillation (QPO) observations of H1743-322 throughout the Rossi X-ray Timing Explorer era. We find that, while different outbursts ...have significant flux differences, they show consistent positive correlations between the QPO fractional rms amplitude and nonthermal fraction of the emission, which indicate an independence of the intrinsic QPO rms on individual outburst brightnesses in H1743-322. However, the dependence of the QPO rms on frequency is different between the outburst rise and decay phases, where the QPO fractional rms of the decay phase is significantly lower than that of the rise phase at low frequencies. The spectral analysis also reveals different ranges of coronal temperature between the two outburst stages. A semiquantitative analysis shows that the Lense–Thirring precession model could be responsible for the QPO rms differences, requiring a variable coronal geometric shape. However, the variable-Comptonization model could also account for the findings. The fact that the rms differences and the hysteresis traces in the hardness–intensity diagram accompany each other indicates a connection between the two phenomena. By correlating the findings with QPO phase lags and the quasi-simultaneous radio flux previously published, we propose there could be corona-jet transitions in H1743-322 similar to those that have been recently reported in GRS 1915+105.
Abstract We present imaging and spectroscopic diagnostics of a long filament during its formation with the observations from the Chinese H α Solar Explorer and Solar Dynamics Observatory. The seed ...filament first appeared at about 05:00 UT on 2022 September 13. Afterward, it grew gradually and connected to another filament segment nearby, building up a long filament at about 20:00 UT on the same day. The CHASE H α spectra show an obvious centroid absorption with mild broadening at the main spine of the long filament, which is interpreted as evidence of filament material accumulation. More interestingly, near the footpoints of the filament, persistent redshifts have been detected in the H α spectra during the filament formation, indicating continuous drainage of filament materials. Furthermore, through inspecting the extreme-ultraviolet (EUV) images and magnetograms, it was found that EUV jets and brightenings appeared repeatedly at the junction of the two filament segments, where opposite magnetic polarities converged and canceled each other continuously. These results suggest the occurrence of intermittent magnetic reconnection that not only connects magnetic structures of the two filament segments but also supplies cold materials for the filament channel likely by the condensation of injected hot plasma, even though a part of the cold materials falls down to the filament footpoints at the same time.
Magnon transistors that can effectively regulate magnon transport by an electric field are desired for magnonics, which aims to provide a Joule-heating free alternative to the conventional ...electronics owing to the electric neutrality of magnons (the key carriers of spin-angular momenta in the magnonics). However, also due to their electric neutrality, magnons have no access to directly interact with an electric field and it is thus difficult to manipulate magnon transport by voltages straightforwardly. Here, we demonstrated a gate voltage (V_{g}) applied on a nonmagnetic metal and magnetic insulator (MI) interface that bent the energy band of the MI and then modulated the probability for conduction electrons in the nonmagnetic metal to tunnel into the MI, which can consequently enhance or weaken the spin-magnon conversion efficiency at the interface. A voltage-controlled magnon transistor based on the magnon-mediated electric current drag (MECD) effect in a Pt-Y_{3}Fe_{5}O_{12}-Pt sandwich was then experimentally realized with V_{g} modulating the magnitude of the MECD signal. The obtained efficiency (the change ratio between the MECD voltage at ±V_{g}) reached 10%/(MV/cm) at 300 K. This prototype of magnon transistor offers an effective scheme to control magnon transport by a gate voltage.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
Since their development, cell-penetrating peptides (CPPs) have been used as delivery vehicles for various genetic or therapeutic agents; however, the uptake mechanisms of CPPs and the delivery ...details are still unclear. Understanding the mechanisms of cellular internalization of CPPs facilitate their development of CPPs as gene delivery vectors. In the present study, we evaluated the internalization process of a previously designed CPP, STR-KV, complexed with small interference RNA (siRNA) targeting at the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene. Using heparin treatment and chemical endocytic inhibitors, we elucidated that the electrostatic interaction of STR-KV/siRNA complex with heparin sulfate proteoglycans at the cell membrane surface triggered the energy-independent uptake of the majority of the complexes, which most likely through a direct translocation pathway. The intracellular trafficking and internalization kinetics observed by confocal microscopy also confirmed that the complex was uptaken through a nonendocytic pathway.
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IJS, KILJ, NUK, PNG, UL, UM
Background
There is significant interest and controversy surrounding the effect of restrictive fluid management on outcomes in major gastrointestinal surgery. This has been most studied in colorectal ...surgery, although the literature relating to pancreaticoduodenectomy (PD) patients is growing. The aim of this paper was to generate a comprehensive review of the available evidence for restrictive perioperative fluid management strategies and outcomes in PD.
Methods
MEDLINE/PubMed, Embase, and the Cochrane Library were searched from inception to April 2017. A review protocol was utilized and registered with PROSPERO. Primary citations that evaluated perioperative fluid management in PD, including those as part of a clinical pathway, were considered. The primary outcome was postoperative pancreatic fistula (POPF). Secondary outcomes included delayed gastric emptying (DGE), complication rate, length of stay (LOS), mortality, and readmission.
Results
A total of six studies involving 846 patients were included (2009–2015), of which four were RCTs. Pooled analysis of RCTs and high-quality observational studies found no effect of restrictive intraoperative fluid management on POPF, DGE, complication rate, LOS, mortality, and readmission. Only one study assessed postoperative fluid management exclusively and found prolonged LOS in patients in the restricted fluid group.
Conclusion
Based on results of RCTs and high-quality observational studies, intraoperative fluid restriction in PD has not been shown to significantly affect postoperative outcomes. There are too few studies assessing postoperative fluid management to draw conclusions at this time.
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EMUNI, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A laminated architecture with uniform dispersed graphene nanoflakes (GNFs) was elaborated in pure Ti matrix via a novel spray deposition method in conjunction with low-temperature consolidation ...strategy. The intrinsic structure of the aligned interlaminar GNFs was well-retained in the whole fabrication processes, and the appropriate interface reaction introduced a strong bonding between GNFs and Ti layers. In particular, the as-designed composite with 0.23 vol% GNFs exhibited the enhanced strength (+48.8% compared with the pure Ti laminates) without sacrifice in ductility. In-situ tensile tests indicated that the GNFs and interfacial TiC could effectively inhibited cracks propagation and relieved the strain concentration. The strengthening and toughening effects were induced by the synergetic effect of uniform dispersion, firmly interface bonding and laminated architecture. Together they act in concert to render outstanding mechanical performance. This study will highlight a simple and feasible route towards well balance between strength and ductility in Ti-based composites, and informative for achieving high-performance in nano-carbon/Ti system.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Van der Waals (vdW) magnet heterostructures have emerged as new platforms to explore exotic magnetic orders and quantum phenomena. Here, we study heterostructures of layered antiferromagnets, CrI
and ...CrCl
, with perpendicular and in-plane magnetic anisotropy, respectively. Using magneto-optical Kerr effect microscopy, we demonstrate out-of-plane magnetic order in the CrCl
layer proximal to CrI
, with ferromagnetic interfacial coupling between the two. Such an interlayer exchange field leads to higher critical temperature than that of either CrI
or CrCl
alone. We further demonstrate significant electric-field control of the coercivity, attributed to the naturally broken structural inversion symmetry of the heterostructure allowing unprecedented direct coupling between electric field and interfacial magnetism. These findings illustrate the opportunity to explore exotic magnetic phases and engineer spintronic devices in vdW heterostructures.
ABSTRACT
SN 2018hti was a very nearby (z = 0.0614) superluminous supernova with an exceedingly bright absolute magnitude of −21.7 mag in r band at maximum. The densely sampled pre-maximum light ...curves of SN 2018hti show a slow luminosity evolution and constrain the rise time to ∼50 rest-frame d. We fitted synthetic light curves to the photometry to infer the physical parameters of the explosion of SN 2018hti for both the magnetar and the CSM-interaction scenarios. We conclude that one of two mechanisms could be powering the luminosity of SN 2018hti; interaction with ∼10 M⊙ of circumstellar material or a magnetar with a magnetic field of Bp∼ 1.3 × 1013 G, and initial period of Pspin∼ 1.8 ms. From the nebular spectrum modelling we infer that SN 2018hti likely results from the explosion of a ${\sim}40\, \mathrm{M}_\odot$ progenitor star.
Purpose: To assess visual outcomes and patient satisfaction for senior resident-performed immediate sequential bilateral cataract surgery (ISBCS) versus delayed sequential bilateral cataract surgery ...(DSBCS) during the COVID-19 pandemic, when minimizing healthcare-related exposures for patients and providers are paramount. Methods: This was a pilot retrospective cohort study of all ISBCS and DSBCS patients who underwent senior resident-performed cataract surgery from May to September 2020 at a single academic institution. Outcome measures were final corrected distance visual acuity (CDVA), final manifest refraction (MRx), intraoperative and postoperative complications rates, total number of visits, and patient satisfaction assessed postoperatively by telephone questionnaire. Results: Twenty-two eyes of 14 patients and 56 eyes of 28 patients underwent senior resident-performed ISBCS and DSBCS, respectively. Final CDVA was 20/25 or better in 21 (95%) ISBCS and 51 (91%) DSBCS eyes (P = 0.670). Deviation of final MRx from target refraction was within 0.50 D in 17 (77%) ISBCS and 47 (84%) DSBCS eyes (P = 0.522). There was no significant difference in intraoperative (P = 1.000) or postoperative (P = 1.000) complications. ISBCS patients averaged 3.5 fewer visits than DSBCS patients (5.9 vs 9.5, P < 0.001). All ISBCS and 20 DSBCS patients (87%) reported they were "very satisfied" or "satisfied" with their experience (P = 0.701). Five of six senior residents responded that they preferred performing ISBCS over DSBCS. Conclusion: This early experience suggests that senior resident-performed ISBCS is as safe and effective as DSBCS, with the added benefit of averaging fewer in-person visits. Residency programs should consider offering senior resident-performed ISBCS to select patients during the COVID-19 pandemic.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Chen P, An L, Zhang Z. Infect Drug Resist. 2023;16:1573-1578. Page 1575, paragraph two, line 10, the text "(600 mg IV q12d)" should read "(600 mg IV q12h)". Page 1575, paragraph two, line 12, the ...text "(400 mg PO q12d)" should read "(400 mg PO q12h)". Page 1576, paragraph five, line three, the text "contezolid 400 mg q12d" should read "contezolid 400 mg q12h". Page 1576, paragraph five, line six, the text "recommended dose of 800 mg q12d" should read "recommended dose of 800 mg q12h". The authors apologize for these errors and any confusion it may have caused the reader.
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