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1.
J Chem Phys ; 159(21)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38038712

RESUMO

In Paper I [H. Francisco, A. C. Cancio, and S. B. Trickey, J. Chem. Phys. 159, 214102 (2023)], we gave a regularization of the Tao-Mo exchange functional that removes the order-of-limits problem in the original Tao-Mo form and also eliminates the unphysical behavior introduced by an earlier regularization while essentially preserving compliance with the second-order gradient expansion. The resulting simplified, regularized (sregTM) functional delivers performance on standard molecular and solid state test sets equal to that of the earlier revised, regularized Tao-Mo functional. Here, we address de-orbitalization of that new sregTM into a pure density functional. We summarize the failures of the Mejía-Rodríguez and Trickey de-orbitalization strategy [Phys. Rev. A 96, 052512 (2017)] when used with both versions. We discuss how those failures apparently arise in the so-called z' indicator function and in substitutes for the reduced density Laplacian in the parent functionals. Then, we show that the sregTM functional can be de-orbitalized somewhat well with a rather peculiarly parameterized version of the previously used deorbitalizer. We discuss, briefly, a de-orbitalization that works in the sense of reproducing error patterns but that apparently succeeds by cancelation of major qualitative errors associated with the de-orbitalized indicator functions α and z, hence, is not recommended. We suggest that the same issue underlies the earlier finding of comparatively mediocre performance of the de-orbitalized Tao-Perdew-Staroverov-Scuseri functional. Our work demonstrates that the intricacy of such two-indicator functionals magnifies the errors introduced by the Mejía-Rodríguez and Trickey de-orbitalization approach in ways that are extremely difficult to analyze and correct.

2.
J Chem Phys ; 159(21)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38038713

RESUMO

The revised, regularized Tao-Mo (rregTM) exchange-correlation density functional approximation (DFA) [A. Patra, S. Jana, and P. Samal, J. Chem. Phys. 153, 184112 (2020) and Jana et al., J. Chem. Phys. 155, 024103 (2021)] resolves the order-of-limits problem in the original TM formulation while preserving its valuable essential behaviors. Those include performance on standard thermochemistry and solid data sets that is competitive with that of the most widely explored meta-generalized-gradient-approximation DFAs (SCAN and r2SCAN) while also providing superior performance on elemental solid magnetization. Puzzlingly however, rregTM proved to be intractable for de-orbitalization via the approach of Mejía-Rodríguez and Trickey [Phys. Rev. A 96, 052512 (2017)]. We report investigation that leads to diagnosis of how the regularization in rregTM of the z indicator functions (z = the ratio of the von-Weizsäcker and Kohn-Sham kinetic energy densities) leads to non-physical behavior. We propose a simpler regularization that eliminates those oddities and that can be calibrated to reproduce the good error patterns of rregTM. We denote this version as simplified, regularized Tao-Mo, sregTM. We also show that it is unnecessary to use rregTM correlation with sregTM exchange: Perdew-Burke-Ernzerhof correlation is sufficient. The subsequent paper shows how sregTM enables some progress on de-orbitalization.

3.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929235

RESUMO

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

4.
Acta Ortop Mex ; 33(6): 352-356, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-32767875

RESUMO

BACKGROUND: Reducing blood loss and transfusions in patients operated on primary TKR is associated with a better clinical and functional outcome. The use of Tranexamic Acid (ATX) is one of the methods used to decrease that bleeding. MATERIAL AND METHODS: Results in Hb, Hto, rate of bleeding and transfusion, surgical time and pain between groups A (with ATX) and group B (without tranexamic acid) after TKR are compared. Results: Statistically significant differences were found during surgery and perisurgical bleeding, in the decrease of Hb at 24 hours, transfusion rate, surgical time and pain to wandering in favor of group A. DISCUSSION: There are no published studies in Mexico on the use of ATX in patients operated on TKR. We consider its use to be increasingly common, the optimal dose and route of administration remains a controversial topic. CONCLUSION: The use of ATX in the proposed scheme is safe and effective in reducing the rate of bleeding and transfusions in patients operated on ATR.


INTRODUCCIÓN: La reducción de la pérdida sanguínea y de las transfusiones en pacientes operados de artroplastía total de rodilla (ATR) primaria se asocia a un mejor resultado clínico y funcional. El uso de ácido tranexámico (ATX) es uno de los métodos utilizados para disminuir ese sangrado. MATERIAL Y MÉTODOS: Se compararon los resultados en hemoglobina (Hb), hematocrito (Hto), tasa de sangrado y de transfusión, tiempo quirúrgico y dolor entre los grupos A (con ATX) y grupo B (sin ATX) posterior a la ATR. RESULTADOS: Se encontraron diferencias estadísticamente significativas en la disminución del sangrado transquirúrgico y periquirúrgico global, en la disminución de la Hb a las 24 horas, en la tasa de transfusión, en el tiempo quirúrgico y en el dolor a la deambulación a favor del grupo A. DISCUSIÓN: En México no hay literatura publicada sobre el uso de ATX en pacientes operados de ATR. A pesar del uso cada vez más común del ATX, la mejor dosis y vía de administración sigue siendo un tema controversial. CONCLUSIÓN: El uso de ATX en el esquema propuesto es un método seguro y eficaz para disminuir la tasa de sangrado y de transfusiones en los pacientes operados de ATR.


Assuntos
Antifibrinolíticos , Artroplastia do Joelho , Perda Sanguínea Cirúrgica , Humanos , México , Hemorragia Pós-Operatória , Ácido Tranexâmico
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