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ABSTRACT: A duration ground-motion model for crustal earthquakes based on the normalized Arias intensity (IA) is developed. Two sets of seismological simulations are used to constrain the form and scaling of the duration model. Simulations using a 3D crustal model show that an additive model for the source, path, and site terms captures the physical behavior of duration better than a multiplicative model for the site term. Stochastic finite-fault simulations are used to constrain the saturation of the large-magnitude scaling at short distances. The duration model is developed in two parts: a duration model for the time interval between 5% and 75% of the normalized Arias intensity (D5−75) and a duration model for the ratio of the D5−X/D5−75 duration for X values from 10 to 95. Together, these two models provide a more complete description of the evolution of the seismic energy with time than a single duration metric. A new aspect of the statistical model for duration is the inclusion of a random effect for the path term in addition to random effects for the source and site terms. The source and site random effects are modeled as scale factors on the duration, whereas the path-term random effect is a scale factor on the distance slope. The distribution of the duration residuals has a skewness that is between the skewness of a lognormal distribution and the symmetry of a normal distribution. The final duration aleatory variability is modeled by a power-normal distribution with an exponent of 0.3, which accounts for the amplitude dependence of the aleatory variability of the duration with smaller aleatory variability for large-magnitude events and larger aleatory variability for small-magnitude events as compared to the variability from a lognormal distribution.

Abstract There is no reason why the gauge symmetry extension is family universal as in the standard model and the most well-motivated models, e.g. left-right symmetry and grand unification. Hence, we propose a simplest extension of the standard model – a flavor-dependent U(1) gauge symmetry – and find the new physics insight. For this aim, the U(1) charge, called X, is expressed as $$X=x B+y L$$ X = x B + y L in which x and y are free parameters as functions of flavor index, e.g. for a flavor i they take $$x_i$$ x i and $$y_i$$ y i respectively, where B and L denote normal baryon and lepton numbers. Imposing a relation involved by the color number 3, i.e. $$-x_{1,2,\ldots ,n}=x_{n+1,n+2,\ldots ,n+m}=3y_{1,2,\ldots ,n+m}\equiv 3z$$ - x 1 , 2 , … , n = x n + 1 , n + 2 , … , n + m = 3 y 1 , 2 , … , n + m ≡ 3 z , for arbitrarily nonzero z, we achieve a novel U(1) theory with implied X-charge. This theory not only explains the origin of the number of observed fermion families but also offers a possible solution for both neutrino mass and dark matter, which differs from $$B-L$$ B - L extension. Two typical models based on this idea are examined, yielding interesting results for flavor-changing neutral currents and particle colliders, besides those of neutrino mass and dark matter.

Abstract The $$SU(3)_L\otimes U(1)_X$$ S U ( 3 ) L ⊗ U ( 1 ) X symmetry actually studied is directly broken to the electroweak symmetry $$SU(2)_L\otimes U(1)_Y$$ S U ( 2 ) L ⊗ U ( 1 ) Y by a Higgs triplet, predicting a relevant new physics at TeV scale. This work argues, by contrast, that the higher weak isospin $$SU(3)_L$$ S U ( 3 ) L might be broken at a high energy scale, much beyond 1 TeV, by a Higgs octet to an intermediate symmetry $$SU(2)_L\otimes U(1)_{T_8}$$ S U ( 2 ) L ⊗ U ( 1 ) T 8 at TeV, before the latter $$U(1)_{T_8}$$ U ( 1 ) T 8 recombined with $$U(1)_X$$ U ( 1 ) X defines (i.e., broken to) $$U(1)_Y$$ U ( 1 ) Y by a Higgs singlet. The new physics coupled to $$SU(3)_L$$ S U ( 3 ) L breaking phase is decoupled, whereas what remains is a novel family-nonuniversal abelian model, $$U(1)_{T_8}\otimes U(1)_X$$ U ( 1 ) T 8 ⊗ U ( 1 ) X , significantly overhauling the standard model as well as yielding consistent results for neutrino mass, dark matter, W-mass anomaly, and FCNC, differently from the usual 3-3-1 model.

Abstract Quark has an electric charge either $$-1/3$$ - 1 / 3 or 2/3 and a baryon number 1/3, where the divisions 3’s match the color number. Although the electric charge and the baryon number have a nature distinct from the color charge, the matching is necessary for the standard model or a relevant $$B-L$$ B - L extension consistent at quantum level, since the relevant anomaly $$[SU(2)_L]^2U(1)_A$$ [ S U ( 2 ) L ] 2 U ( 1 ) A for $$A=Y$$ A = Y or $$B-L$$ B - L must vanish. If elementary particles have a new U(1) charge differently from A, such anomaly is not cancelled for each family. However, if we demand that the anomaly is cancelled over all families, this relates the color number to the family number instead of the electric charge and baryon number, and interestingly the family number guides us to a novel U(1) theory. We will discuss the implication of this theory for neutrino mass, recent W-boson mass anomaly, FCNC, and particle colliders.

Public investment in education and training occupies an important proportion in Vietnam public budget, approximately 20%, equivalent to 5% GDP. Public investment in education and training has many positive benefits and impact on the economy and society by contributing to economic growth, by improving the national productivity, people's qualification and intellectual level well as reducing unemployment, poverty in a country. On the basis of an empirical analysis in Vietnam, this paper proposes several relevant recommendation for Vietnam government to improve the performance of public investment in education and training by making contribution to ensure suitable investment structure as well as uphold important role of education and training to the development of the economy and society.

Abstract Hedera nepalensis is commonly used as a traditional medicine for the treatment of several diseases. In this research, the efficient characterization of chemical constituents, especially triterpenoid saponins, contained in H. nepalensis extract was established by applying ultra‐high‐performance liquid chromatography‐quadrupole time‐of‐flight tandem mass spectrometry method (UHPLC‐Q‐TOF‐MS/MS). As a result, a total of 45 compounds including 21 triterpene saponins were tentatively elucidated based on MS and MS/MS data, in which eight structures have been reported for the first time. This study provided an efficient analysis strategy to rapidly determine the chemical constituents and laid a foundation for future study of H. nepalensis planted in Northern Vietnam and other Hedera species.

Abstract The recent precision measurement of the W-boson mass reveals an exciting hint for the new physics as of the 3-3-1 model. We indicate that the 3-3-1 model contains distinct sources by itself that may cause the W-mass deviation, as measured, such as the tree-level Z- $$Z'$$ Z ′ mixing, the tree-level W-Y and Z- $$Z'$$ Z ′ -X mixings, as well as the non-degenerate gauge vector (X, Y) and new Higgs doublets. We point out that the gauge vector doublet negligibly contributes to this mass shift, whereas the rest of the effects with tree-level mixings governed by Z- $$Z'$$ Z ′ and new Higgs doublets are significant. A discussion of scalar sextet contributions is also given.

Objectives: To translate and adapt the Diabetic Self-care Knowledge Questionnaire-30 (DSCKQ-30) questionnaire to be suitable for Vietnamese conditions and culture. To examine the reliability and validity of the Vietnamese version of the DSCKQ-30 questionnaire. Material and Methods: The questionnaire was forward translated, from English into Vietnamese and vice versa, by four independent translators. After that, an expert panel resolved any disagreements in translation regarding 4 criteria: semantics, idioms, experiences and concepts. The questionnaire then underwent a pilot study, on a sample of 100 DM patients to assess its clarity and readability; from June 1, 2021, to June 15, 2021. Finally, a test-retest study was conducted on a sample of 279 patients, over one month to examine internal consistency, stability and construct validity of the questionnaire; from July 1, 2021 to July 30, 2021. This study was approved by the Research Ethics Committee of the Thai Nguyen National Hospital. Results: The Vietnamese translated diabeté self-care knowledge questionnaire had content validity of 1.00, Cronbach’s alpha of 0.899 and Kappa coefficient of 0.700 or greater, except for question 15: with a Kappa coefficient of 0.658 (acceptable). Conclusion: The translated, adapted version of the DSCKQ-30 is valid, reliable and a feasible tool for practice, education and research in the future.

Since the electric charge in the standard model is theoretically not quantized, we may have a variant of it, called dark charge. Similar to the electric charge, the dark charge neither commutes nor closes algebraically with SU(2)L. The condition of algebraic closure leads to a novel gauge extension, SU(2)L⊗U(1)Y⊗U(1)N, where Y and N determine the electric and dark charges, respectively, apart from the color group. We argue that the existence of the dark charge, thus N, leads to novel scenarios of multi-component dark matter, in general. The dark matter stability is determined by a residual (or dark charge) gauge symmetry isomorphic to an even Zk discrete group, where k is specified dependent on the value of the neutrino dark charge. This residual symmetry divides the standard model particles into distinct classes, which possibly accommodate dark matter, but each dark matter candidate cannot decay due to the color and electric charge conservation. We analyze in detail three specific models according to k=2,4,6 and determine the simplest dark matter candidates. For small U(1)N coupling, the two-component dark matter scenarios implied by the dark charge successfully explain the dark matter relic density and the recent XENON1T excess, as well as the beam dump, neutrino scattering, and astrophysical bounds. Otherwise, for large U(1)N coupling, we have multi-WIMPs coexisted beyond the weak scale.

Abstract We present the features of the fully flipped 3-3-1-1 model and show that this model leads to dark matter candidates naturally. We study two dark matter scenarios corresponding to the triplet fermion and singlet scalar candidates, and we determine the viable parameter regimes constrained from the observed relic density and direct detection experiments.