Miracle-dz/UniFAR-FTUs huggingface dataset:
Stability of a pair of co-rotating vortices with axial flow

The three-dimensional linear temporal stability properties of a flow composed of two corotating q-vortices (also called Batchelor vortices) are predicted by numerical stability analysis. As for the corresponding counter-rotating case, when the axial flow parameter is increased, different instability modes are observed and identified as a combination of resonant Kelvin modes of azimuthal wavenumbers m and m+2 within each vortex. In particular, we show that the sinuous mode, which is the dominant instability mode without axial flow, is stabilized in the presence of a moderate axial flow. Different types of mode with a large amplitude in the critical layer are also identified. For small separation distances (above the merging threshold), unstable eigenmodes, corresponding to axial wavenumbers that cannot be easily identified with simple resonant interactions of Kelvin modes, are also observed. Their growth rate is a substantial fraction of the growth rates of low-order resonant modes. The effects of the Reyn.
Symptomatic Chikungunya Virus Infection and Pregnancy Outcomes: A Nested Case-Control Study in French Guiana

During the Chikungunya epidemic in the Caribbean and Latin America, pregnant women were affected by the virus in French Guiana. The question of the impact of the virus on pregnancy was raised because of the lack of scientific consensus and published data in the region. Thus, during the Chikungunya outbreak in French Guiana, a comparative study was set up using a cohort of pregnant women. The objective was to compare pregnancy and neonatal outcomes between pregnant women with Chikungunya virus (CHIKV) infection and pregnant women without CHIKV. Of 653 mothers included in the cohort, 246 mothers were included in the case-control study: 73 had CHIKV fever during pregnancy and 173 had neither fever nor CHIKV during pregnancy. The study did not observe any severe clinical presentation of CHIKV in the participating women. There were no intensive care unit admissions. In addition, the study showed no significant difference between the two groups with regard to pregnancy complications. However, the results showed a potential excess risk of neonatal ICU admission of the newborn when the maternal infection occurred within 7 days before delivery. These results suggest that special attention should be paid to neonates whose mothers were infected with CHIKV shortly before delivery.
Online teaching and learning practices in teacher education after COVID-19: lessons learnt from the literature

ABSTRACT The COVID-19 pandemic forced higher education institutions and teacher education programmes to transition from face-to-face to remote teaching. In this new educational environment, universities and schools had to make changes to address emerging teaching and learning needs. This literature review study provides an overview of research on teaching and learning practices published after the outbreak of COVID-19 in the context of teacher education. It aims to examine their characteristics after the pandemic and analyse issues that have affected their development. Based on the inclusion criteria, 28 papers were considered in the analysis. Findings point to the social and collaborative dimension of teaching, the caring component and the adoption of a more democratic and inclusive approach to teaching and learning. Personal and contextual factors and the challenges encountered related to poor interaction and difficulties in assessing students’ performance are also identified. Implications for rethinking current online teaching and learning practices in the context of teacher education are discussed.
BNNAS++: Towards Unbiased Neural Architecture Search With Batch Normalization

Neural Architecture Search (NAS) achieves significant progress in many computer vision tasks, yet training and searching high-performance architectures over large search space are time-consuming. The NAS with BatchNorm (BNNAS) is an efficient NAS algorithm to speed up the training of supernet ten times over conventional schemes by fixing the convolutional layers and training the BatchNorm only. In this paper, we systematically examine the limitation of the BNNAS and present improved techniques. We observe that the BNNAS is prone to select convolution and fails to find plausible architectures with small FLOPs, especially on the search space with operations other than convolutions. This is because the number of learnable parameters on BatchNorm is imbalanced for different operations, i.e., BatchNorm is only attached to the convolutional layer. To fix the issue, We present the unbiased BNNAS for training. However, our empirical evidence shows that the performance indicator in BNNAS is ineffective on the unbiased BNNAS. To this end, we propose a novel performance indicator, which decomposes the model performance into model expressivity, trainability, and uncertainty, to preserve the rank consistency on the unbiased BNNAS. Our proposed NAS method, named as BNNAS ++, is robust on various search spaces and can efficiently search high-performance architectures with small FLOPs. We validate the effectiveness of BNNAS++ on NAS-Bench-101, NAS-Bench-201, DARTS search space, and MobileNet search space, showing superior performance over existing methods.
MOLECULAR HYDROGEN EMISSION FROM THE BOUNDARIES OF THE TAURUS MOLECULAR CLOUD

We report Spitzer Space Telescope observations of the four lowest rotational transitions of H2 in three portions of the boundary of the Taurus molecular cloud. Emission in the two lowest transitions, S(0) and S(1), was detected in almost all pointing directions, while the S(2) and S(3) lines were marginally detected only after further averaging of data. The widespread detection of lines coming from levels 510 K and 1016 K above the molecular ground state is indicative of gas at a temperature of at least 200 K containing column densities (1–5) × 1018 cm−2 of H2. For the region with the simplest geometry, we have used the Meudon PDR code to model the chemistry, radiative transfer, and excitation of molecular hydrogen. We conclude that models with acceptable values of the UV interstellar radiation field can reproduce the amount of H2 in the lowest excited state, but cannot account for the degree of excitation of the H2. The unexpectedly high degree of excitation of the H2 in the boundary layer of a molecular cloud, which cannot be explained by the presence of stellar sources, points to an enhanced heating rate which may be the result of, e.g., dissipation of turbulence. We have in one boundary region been able to obtain the ortho-to-para ratio (OPR) for H2, which by modeling and possible detection of the S(2) and S(3) lines has a range 1.0 ⩾ OPR ⩾ 0.15, although this result must be treated with caution. The fact that the ortho-to-para ratio is lower than that expected for equilibrium at the gas kinetic temperature may be indicative of circulation of material from cold, purely molecular regions into the boundary layer, possibly due to turbulent diffusion. The explanation of these data may thus be suggestive of processes that are having a significant effect on the structure and evolution of molecular clouds and the star formation that takes place within them.
Subcritical Instability and Hysteresis in a Two-Layer Model.

Abstract A two-layer quasi-geostrophic model forced by surface friction and radiative relaxation to a jetlike wind profile can exist in either a wave-free state or in a finite-amplitude wave state, over a substantial region of the model's parameter space. The friction on the lower layer must be much stronger than the thermal relaxation, and the upper layer must be nearly inviscid, for this behavior to be observed. Consistent with this behavior, weakly unstable waves are found that do not stabilize the flow; instead, their growth rate increases with wave amplitude. We attempt to provide a physical explanation for this behavior in terms of 1) the competition between the stabilizing effect of the lower-layer potential vorticity fluxes and the destabilizing effect of nonlinear critical layer formation associated with the upper-layer fluxes, and 2) the tendency of surface drag to restore the vertical shear at the center of the jet by damping the surface westerlies generated by the baroclinic instability.
The p-Cycle of Holonomic D-modules and Automorphisms of the Weyl Algebra

We construct a correspondence between smooth algebraic Lagrangians in the cotangent bundle of complex affine n-space which satisfy some (co)homology vanishing assumptions and a certain class of holonomic modules over the n-th Weyl algebra. The association goes via reduction mod p. As a consequence, we deduce that the group of Morita autoequivalences of the n-th Weyl algebra is isomorphic to the group of symplectomorphisms of the cotangent bundle of affine space. This generalizes an old theorem of Dixmier (in the case n=1) and settles a conjecture of Belov-Kanel and Kontsevich in general.
The strain effect on critical current in YBCO coated conductors with different stabilizing layers

The tensile strain dependences of the critical current (Ic) in YBa2Cu3O7−δ (YBCO) coated conductors fabricated by using the rolling-assisted biaxially textured Ni–W substrates (RABiTS)–pulsed laser deposition (PLD) method were examined at 77 K and in self magnetic field. Cu and stainless steel layers were used as stabilizers to the YBCO coated conductor, and the effects of stabilizing layers on the strain tolerance of Ic were investigated, compared with the case without a stabilizing layer. The lamination of stabilizer produced an increase in the yield strength and strain tolerance of Ic in coated conductors. All YBCO coated conductors tested showed a reversible strain effect and a peak in the relation between Ic and applied strain. The peak strain of Ic and the irreversible strains for Ic degradation were enhanced when the YBCO coated conductor was laminated with a stabilizing layer. For the case laminated with a stainless steel layer, Ic recovered reversibly until the applied strain reached to about 0.5% and showed its peak at a strain of 0.42%, comparing to the case without a stabilizing layer, which were 0.21% and 0.18%, respectively. It can be predicted that the lamination of a stabilizing layer produced a significant residual compressive strain to the YBCO film during cooling to 77 K, which influenced the axial strain tolerance of YBCO coated conductors. Therefore, the Ic–tensile strain relation in YBCO coated conductors could be explained by a two-stage deformation; stage I is the region where YBCO film behaves elastically and Ic recovers when the stress is released. Stage II is the region where Ic decreases irreversibly attributable to the cracking induced in the YBCO film due to the significant plastic deformation of the substrate or the stabilizing layer.
Adaptive Smith Predictor for Enhanced Stability of Power Hardware-in-the-Loop Setups

The stability and accuracy of power hardware-in-the-loop (PHIL) setups are sensitive to and deteriorated by the dynamics and nonideal characteristics of their power interfaces, such as time delay, noise perturbation, and signal distortion. In this article, a compensation scheme comprising a Smith predictor compensator is proposed to mitigate the impact of time delay on PHIL stability. Furthermore, an online system impedance identification technique is leveraged to enhance the robustness of the compensator and facilitate the compensation scheme with adaptivity to system impedance variation. Analytical assessment, simulation results, and PHIL experimental results are presented to verify the proposed compensation scheme. This scheme enables robust and stable testing of novel power technologies under varying impedance ratios representative of the complex scenarios emerging within the power sector.
R-matrix calculation of the continuum states of carbon monoxide

Calculations on electron collisions with CO+ molecular ion are presented as a function of electron energy and CO+ geometry. Resonance positions and widths are obtained for the low-lying Feshbach resonances in the system. Plots of resonance curves suggest that low-energy dissociative recombination can occur via resonances of 1Π, 1Δ, 3Σ+ and 3Π symmetries. Electron impact electronic excitation is considered both for excitation to the first excited A 2Π state and to yield a dissociation cross section. The latter calculations suggest that the lower of two experimental measurements of this process is likely to be correct. Finally results are presented for bound states in the continuum for both 1Σ− and 3Σ− symmetries.
The Transformative Nature of Residential Immersive Life Skills Programs: Integrating Findings from a Five-Year Prospective Study of Program Opportunities, Youth Experiences, and Outcomes

Youth with disabilities often experience limited opportunities to acquire the life skills needed in adulthood. As a result, life skills programs are provided to support life skill development; however, little is known about the active ingredients of these programs, and the sustainability of their effects over time. Accordingly, the aim was to synthesize the findings of a five-year study examining the opportunities, experiences, and outcomes of residential immersive life skills (RILS) programs for youth with disabilities. A multi-method prospective study was conducted involving 38 youth ages 14 to 21 with disabilities (e.g., cerebral palsy, spina bifida) attending one of three RILS programs held over three summers. Program opportunities, youth experiences, and outcomes (self-determination, self-efficacy) were assessed pre- and post-program and 3 and 12 months post-program using standardized questionnaires. Pre-program, 3-month, and 12-month follow-up interviews were held with youth and parents. This research synthesis integrates the findings from nine published articles that used a variety of qualitative, quantitative, and mixed methods approaches. RILS programs provided rich opportunities for youth to experience meaningful social connections, psychological engagement, and choice and control, which were associated with changes over time in multiple domains related to personal growth and preparation for adulthood. Overall, the findings point to the transformative power of RILS programs to propel new life directions for some youth. By creating opportunities for meaningful, challenging, and supportive experiences fulfilling basic needs for relatedness, competency, and autonomy, RILS programs motivate youth to grow and change. More study is needed of program opportunities and capacity-enhancing experiences, as well as longitudinal studies of youth life outcomes. RILS programs have appreciable value in preparing youth for the transition to adult roles and responsibilities.
UNCONSTRAINED MINIMIZATION BY COMBINING THE DYNAMIC AND CONJUGATE GRADIENT METHODS

ABSTRACT The author has recently developed a gradient-only dynamic method for unconstrained minimization. The main drawback of this method is, that in spite of rapid motion towards the neighbourhood of a local minimum, the final convergence is slow. To improve the situation the possibility of switching from the dynamic method to a conjugate qradient type method near the minimum is investigated. The Fletcher-Reeves conjugate gradient method is applied in a way in which only gradient evaluations are used by exploiting an Euler—trapezium integration scheme. The numerical results obtained are promising, indicating the combined method to be competitive for problems of high dimensionality and where the gradient evaluations are re1atively inexpensive.
Variational Data Assimilation with a Semi-Lagrangian Semi-implicit Global Shallow-Water Equation Model and Its Adjoint

Abstract An adjoint model is developed for variational data assimilation using the 2D semi-Lagrangian semi-implicit (SLSI) shallow-water equation global model of Bates et al. with special attention being paid to the linearization of the interpolation routines. It is demonstrated that with larger time steps the limit of the validity of the tangent linear model will be curtailed due to the interpolations, especially in regions where sharp gradients in the interpolated variables coupled with strong advective wind occur, a synoptic situation common in the high latitudes. This effect is particularly evident near the pole in the Northern Hemisphere during the winter season. Variational data assimilation experiments of “identical twin” type with observations available only at the end of the assimilation period perform well with this adjoint model. It is confirmed that the computational efficiency of the semi-Lagrangian scheme is preserved during the minimization process, related to the variational data assimilat.
Development of 200-GHz to 2.7-THz multiplier chains for submillimeter-wave heterodyne receivers

Several astrophysics and Earth observation space missions planned for the near future will require submillimeter-wave heterodyne radiometers for spectral line observations. One of these, the Far InfraRed and Submillimeter Telescope will perform high-sensitivity, high-resolution spectroscopy in the 400 to 2700 GHz range with a seven channel super- conducting heterodyne receiver complement. The local oscillators for all these channels will be constructed around state-of-the-art GaAs power amplifiers in the 71 to 115 GHz range, followed by planar Schottky diode multiplier chains. The Jet Propulsion Laboratory is responsible for developing the multiplier chains for the 1.2, 1.7, and 2.7 THz bands. This paper will focus on the designs and technologies being developed to enhance the current state- of-the-art, which is based on discrete planar or whisker contacted GaAs Schottky diode chips mounted in waveguide blocks. We are proposing a number of new planar integrated circuit and device topologies to implement multipliers at these high frequencies. Approaches include substrateless, framed and frameless GaAs membrane circuitry with single, and multiple planar integrated Schottky diodes. Circuits discussed include 200 and 400 GHz doublers, a 1.2 THz tripler and a 2.4 THz doubler. Progress to date, with the implications of this technology development for future Earth and space science instruments, is presented.
The symbiotic roles of empirical experimentation and thought experimentation in the learning of physics

This study was an attempt to identify the epistemological roots of knowledge when students carry out hands‐on experiments in physics. We found that, within the context of designing a solution to a stated problem, subjects constructed and ran thought experiments intertwined within the processes of conducting physical experiments. We show that the process of alternating between these two modes — empirically experimenting and experimenting in thought — leads towards a convergence on scientifically acceptable concepts. We call this process mutual projection. In the process of mutual projection, external representations were generated. Objects in the physical environment were represented in an imaginary world and these representations were associated with processes in the physical world. It is through this coupling that constituents of both the imaginary world and the physical world gain meaning. We further show that the external representations are rooted in sensory interaction and constitute a semi‐symbolic pictorial communication system, a sort of primitive ‘language’, which is developed as the practical work continues. The constituents of this pictorial communication system are used in the thought experiments taking place in association with the empirical experimentation. The results of this study provide a model of physics learning during hands‐on experimentation.
Prognostic value of lactate dehydrogenase in non-small cell lung cancer patients with brain metastases: a retrospective cohort study

Background At present, although there are some known molecular markers for the prognosis of non-small cell lung cancer (NSCLC) brain metastases, but there are still shortcomings in sensitivity and specificity. Lactate dehydrogenase (LDH) is one of the key enzymes involved in malignancy vital glycolytic pathway. Elevated serum LDH levels are reported significantly associated with a poor prognosis in various malignancies. However, there is currently no consensus regarding the prognostic value of LDH in NSCLC patients with brain metastases. Methods We retrospectively analyzed 224 patients diagnosed with lung cancer brain metastases between January 2006 and June 2020 after excluding patients meeting combined with other malignancies and inaccurate clinical information. The LDH cutoff values were obtained using a restricted cubic spline (RCS) model, and the patients were divided into two groups according to the optimal cut-off value (180 U/L). 107 patients with LDH ≤180 (47.77%) and 117 patients with LDH >180 (52.23%) were identified. Univariate and multivariate logistic regression analyses were performed to identify the risk factors. The overall survival (OS) time was defined as the time from the first diagnosis of brain metastases to the last follow-up or death. Of the included patients, 147 survived and 77 died. The Kaplan-Meier method was used to illustrate the OS difference between the two groups. Finally, sensitivity analysis was employed to evaluate the robustness of the results. Results The OS rate was significantly lower in the high LDH group versus the low LDH group (P=0.009). The median survival times of the high and low LDH groups were approximately 16 and 33 months, respectively. Multivariate analysis showed that high LDH was associated with a significantly worse OS [adjusted hazard ratio (aHR), 1.567; 95% confidence interval (CI): 1.058 to 2.32, P=0.025] with adjustment for covariables that P<0.05 in univariate analysis. Sensitivity analysis indicated that the results of this study are robust, despite potential unmeasured confounders. Conclusions High level of serum LDH indicates poor prognosis for patients with NSCLC brain metastases. This finding may provide useful prognostic information for patients and clinicians to choose more aggressive treatment strategies.
Nurturing Deep Tech to Solve Social Problems: Learning from COVID-19 mRNA Vaccine Development

In mRNA vaccines against COVID-19, a new technology that had never been used for approved drugs was applied and succeeded in rapid clinical use. The development and application of new technologies are critical to solving emerging public health problems therefore it is important to understand which factors enabled the rapid development of the COVID-19 mRNA vaccines. This review discusses administrative and technological aspects of rapid vaccine development. In the technological aspects, I carefully examined the technology and clinical development histories of BioNTech and Moderna by searching their publication, patent application and clinical trials. Compared to the case of Japanese company that has not succeeded in the rapid development of mRNA vaccine, years of in-depth technology research and clinical development experience with other diseases and viruses were found to have enhanced BioNTech and Moderna’s technological readiness and contributed to rapid vaccine development against COVID-19 in addition to government administrative support. An aspect of the investments that supported the long-term research and development of mRNA vaccines is also discussed.