10 research outputs found
Chirality selective magnon-phonon hybridization and magnon-induced chiral phonons in a layered zigzag antiferromagnet
Two-dimensional (2D) magnetic systems possess versatile magnetic order and
can host tunable magnons carrying spin angular momenta. Recent advances show
angular momentum can also be carried by lattice vibrations in the form of
chiral phonons. However, the interplay between magnons and chiral phonons as
well as the details of chiral phonon formation in a magnetic system are yet to
be explored. Here, we report the observation of magnon-induced chiral phonons
and chirality selective magnon-phonon hybridization in a layered zigzag
antiferromagnet (AFM) FePSe. With a combination of magneto-infrared and
magneto-Raman spectroscopy, we observe chiral magnon polarons (chiMP), the new
hybridized quasiparticles, at zero magnetic field. The hybridization gap
reaches 0.25~meV and survives down to the quadrilayer limit. Via first
principle calculations, we uncover a coherent coupling between AFM magnons and
chiral phonons with parallel angular momenta, which arises from the underlying
phonon and space group symmetries. This coupling lifts the chiral phonon
degeneracy and gives rise to an unusual Raman circular polarization of the
chiMP branches. The observation of coherent chiral spin-lattice excitations at
zero magnetic field paves the way for angular momentum-based hybrid phononic
and magnonic devices
Non-Standard Errors
In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants
Estudio histoquimico y morfometrico de la poblacion fibrilar del musculo diafragma en distintas especies domesticas
Available from Centro de Informacion y Documentacion Cientifica CINDOC. Joaquin Costa, 22. 28002 Madrid. SPAIN / CINDOC - Centro de Informaciòn y Documentaciòn CientìficaSIGLEESSpai
I bombardamenti dell'Aviazione Legionaria su Barcellona nel quadro dell'anomala linea di comando dell'intervento fascista in Spagna, in Aronica, Daniela (a cura di), Mussolini alla Guerra di Spagna: uomini, mezzi, propaganda, Ibis Edizioni, Como-Pavia 2018, da p. 52 a pag. 96.
Il contributo analizza la struttura di comando dell'Aviazione Legionaria, le cause e la realizzazione del bombardamento sulla città di Barcellona 16-18 marzo 1938
Non-Standard Errors
URL des documents de travail : https://centredeconomiesorbonne.cnrs.fr/publications/Documents de travail du Centre d'Economie de la Sorbonne 2021.33 - ISSN : 1955-611XVoir aussi ce document de travail sur SSRN: https://ssrn.com/abstract=3981597In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in sample estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: non-standard errors. To study them, we let 164 teams test six hypotheses on the same sample. We find that non-standard errors are sizeable, on par with standard errors. Their size (i) co-varies only weakly with team merits, reproducibility, or peer rating, (ii) declines significantly after peer-feedback, and (iii) is underestimated by participants
Spontaneous Resolution Of Syringomyelia Without Chiari Malformation - Case Report
A 30-year-old woman presented with a cervical syrinx manifesting as hemihypesthesia. Neuroimaging found no evidence of Chiari malformation or tight cisterna magna. Serial magnetic resonance imaging studies over a 6-year period demonstrated spontaneous and complete resolution of the syrinx accompanied by an asymptomatic clinical course. The natural history of syringomyelia is highly unpredictable. The outcome of surgical treatment for patients with syringomyelia is not always satisfactory, so the indications for surgery are controversial. Spontaneous resolution of syringomyelia unrelated with foramen magnum lesion has various causes. Close follow up of the patient is necessary to monitor for recurrence.WoSScopu
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Non-standard errors
In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants