Remembering the 1918 Influenza Pandemic: Missouri Education Policy and Lessons for COVID-19

Amid the disruptions of COVID-19 are opportunities to reimagine schooling and education. Taking a historical perspective, this article analyzes education policy following an earlier pandemic, the influenza pandemic of 1918-19, to explore if and how educational change might be possible. Drawing on primary source analysis of Missouri education policy, I argue that influenza-related policy talk was practically non-existent, and the talk that was present mainly focused on how the flu disrupted, but not changed, school operations. Without policy talk advocating for change, policy action the years following the influenza pandemic continued along the lines of Progressive reforms that were already circulating prior. I conclude with implications of this historical analysis for responding to the current COVID-19 pandemic

A see-saw scenario of an A4A_4 flavour symmetric standard model

A see-saw scenario for an $A_4$ flavour symmetric standard model is presented. The latter, compared with the standard model, has an extended field content adopting now an additional $A_4$ symmetry structure (along with the standard model symmetry). As before, the see-saw mechanism can be realized in several models of different types depending on different ways of neutrino mass generation corresponding to the introduction of new (heavy in general) fields with different symmetry structures. In the present paper, a general description of all these see-saw types is made with a more detailed investigation on type-I models, while for type-II and type-III models a similar strategy can be followed. As within the original see-saw mechanism, the symmetry structure of the standard model fields decides the number and the symmetry structure of the new fields. In a model considered here, the scalar sector consists of three standard-model-Higgs-like iso-doublets ($SU_L(2)$-doublets) forming together an $A_4$-triplet, and three iso-singlets transforming as three singlets (1,$1^{'}$ and $1^{''}$) of $A_4$. In the lepton sector, the three left-handed lepton iso-doublets form an $A_4$-triplet, while the three right-handed charged leptons are either $A_4$-singlets in one version of the model, or components of an $A_4$-triplet in another version. To generate neutrino masses through, say, the type-I see-saw mechanism, it is natural to add four right-handed neutrino multiplets, including one $A_4$-triplet and three $A_4$-singlets. For an interpretation, the model is applied to deriving some physics quantities such as neutrinoless double beta decay effective mass $|\langle m_{ee}\rangle|$, CP violation phase $\delta_{CP}$ and Jarlskog parameter $J_{CP}$, which can be verified experimentally.Comment: LaTeX, 31 pages, 12 figures, 6 tables. V3: some parts modifie

Investigating car purchasing decision-making process using Multi- Objective Optimization Ratio Analysis based Analytical Hierarchy Process Model: An empirical case from Vietnam

This study aims to define and quantify the factors affecting selecting the best car among the market's available alternatives. Many criteria are involved while deciding to purchase the best car from various car models; therefore, car purchasing behaviour is a multi-criteria decision-making problem (MCDM). Proposed criteria are based on the customers’ survey when they are willing to purchase the cars, including Price, Branding, Safety, Performance, Exterior, Fuel efficiency, Maintainance cost, After-Sale Service, and Resale. In this study, the AHP technique calculates each criterion's weight, and then Multi-Objective Optimization Ratio Analysis (MOORA) is employed to rank the car models in a numerical example from Vietnam. The results show that this proposed model can minimize the consumer effort to select a car and make accurate decisions. Furthermore, this study's findings could provide car manufacturers with valuable insight into the criteria that reflect the customer's assessment of the car selection process. JEL: C02, C61, D53, Q1

Mobility Edges in One-dimensional Disordered Aharonov-Bohm Rings

We study numerically the localization properties of the eigenstates of a tight-binding Hamiltonian model for noninteracting electrons moving in a one-dimensional disordered ring pierced by an Aharonov-Bohm flux. By analyzing the dependence of the inverse participation ratio on Aharonov-Bohm flux, energy, disorder strength and system size, we find that all states in the ring are delocalized in the weak disorder limit. The states lying deeply in the band tails will undergo a continuous delocalization-localization transition as the disorder strength in the ring sweeps from the weak to the strong disorder regime

Evaluation of Dental and Skeletal Changes with Sequential Distalization of Maxillary Molars Using Clear Aligners: A preliminary study

Introduction: Class II malocclusions can be treated with appliances such as the pendulum appliance or distal jets to distalize maxillary molars to achieve a Class I molar relationships. It is not clear in the literature whether these clear aligners can distalize maxillary molars, dental tipping, or translation. The objective was to evaluate the dental and skeletal changes in three planes spaces using CBCT scans and compare the treatment changes with a control group of subjects. Methods: Eight Class II division 1 malocclusions patients treated with maxillary molar distalization using clear aligners. Twelve molars were evaluated for tooth movement in three planes of space using CBCT scans. Patients were compared with a control group of untreated subjects from the Bolton Brush study; matched in craniofacial morphology, gender, and treatment length. Sagittal and vertical changes were measured using the Pancherz analysis (Pancherz, 1982). Transverse changes were measured by intermolar widths of the maxillary and mandibular molars. Results: Significant sagittal changes were found with the change in molar relationship (-2.3mm), forward movement of the mandibular incisors (+3.4mm), and mandibular molars (+3.6mm). The treatment changes were compared to control subjects, significant differences were found with the mesial movement of the maxillary molars (0.5mm vs. 5.0mm, Conclusions:Significant dentoalveolar changes including restraint in the forward movement of the maxillary molars can be expected with sequential molar distalization with clear aligners