Backaction in metasurface etalons

We consider the response of etalons created by a combination of a conventional mirror and a metasurface, composed of a periodic lattice of metal scatterers with a resonant response. This geometry has been used previously for perfect absorption, in so-called Salisbury screens, and for hybridization of localized plasmons with Fabry-Perot resonances. The particular aspect we address is if one can assume an environment-independent reflectivity for the metasurface when calculating the reflectivity of the composite system, as in a standard Fabry-Perot analysis, or whether the fact that the metasurface interacts with its own mirror image renormalizes its response. Using lattice sum theory, we take into account all possible retarded dipole-dipole interactions of scatterers in the metasurface amongst each other, and through the mirror. We show that while a layer-by-layer Fabry-Perot formalism captures the main qualitative features of metasurface etalons, in fact the mirror modifies both the polarizability and reflectivity of the metasurface in a fashion that is akin to Drexhage's modification of the radiative properties of a single dipole.Comment: 10 pages, 5 figure

Single-Cell Transcriptomes Reveal a Complex Cellular Landscape in the Middle Ear and Differential Capacities for Acute Response to Infection.

Single-cell transcriptomics was used to profile cells of the normal murine middle ear. Clustering analysis of 6770 transcriptomes identified 17 cell clusters corresponding to distinct cell types: five epithelial, three stromal, three lymphocyte, two monocyte, two endothelial, one pericyte and one melanocyte cluster. Within some clusters, cell subtypes were identified. While many corresponded to those cell types known from prior studies, several novel types or subtypes were noted. The results indicate unexpected cellular diversity within the resting middle ear mucosa. The resolution of uncomplicated, acute, otitis media is too rapid for cognate immunity to play a major role. Thus innate immunity is likely responsible for normal recovery from middle ear infection. The need for rapid response to pathogens suggests that innate immune genes may be constitutively expressed by middle ear cells. We therefore assessed expression of innate immune genes across all cell types, to evaluate potential for rapid responses to middle ear infection. Resident monocytes/macrophages expressed the most such genes, including pathogen receptors, cytokines, chemokines and chemokine receptors. Other cell types displayed distinct innate immune gene profiles. Epithelial cells preferentially expressed pathogen receptors, bactericidal peptides and mucins. Stromal and endothelial cells expressed pathogen receptors. Pericytes expressed pro-inflammatory cytokines. Lymphocytes expressed chemokine receptors and antimicrobials. The results suggest that tissue monocytes, including macrophages, are the master regulators of the immediate middle ear response to infection, but that virtually all cell types act in concert to mount a defense against pathogens

Comment on “Classical description of H(1s) andH∗(n=2) for cross-section calculations relevant to charge-exchange diagnostics”

Cariatore et al. [Phys. Rev. A 91, 042709 (2015)] have introduced a modification of the classical trajectory Monte Carlo (CTMC) method, specially conceived to provide an accurate representation of charge-exchange processes between highly charged ions and H(1s), H ∗ (n=2) . We point out that this new CTMC treatment is based on nonstable initial distributions for H ∗ (n=2) targets and an improper description of the H(1s) targetThis work has been partially supported by Ministerio de Economía y Competitividad (Spain) (Projects No. ENE2011-28200 and No. ENE2014-5432-R

Pengembangan LKPD Berbasis STEM Untuk Menumbuhkan Keterampilan Berpikir Kreatif Siswa

One of learning approach that can be used to practice the skills of creative thinking is a STEM learning approach. It is effective if supported by teaching materials in the form of the worksheets. This study uses research and development methods. The result of the design and content test shows that the product is very decent. Test of attractiveness, convenience, and usefulness performed by students, the attractiveness of the results obtained with a score of 3.16, the convenience with a score of 3.41 and the usefulness with a score of 3.44. The research design is quasi-experimental design in the form of pre-post nonequivalent control group design. The results of the effectiveness test known that the value of n-gain experimental class (0.71)> control class (0.45). It can be concluded that the worksheets by STEM approach have been effective in training students\u27 creative thinking skills. Salah satu pendekatan pembelajaran yang digunakan untuk melatih keterampilan berpikir kreatif adalah pendekatan pembelajaran STEM. Hal tersebut efektif jika didukung dengan bahan ajar berupa LKPD Penelitian ini menggunakan metode penelitian research and development. Telah dilakukan uji validasi terdiri dari uji ahli desain serta uji ahli materi dan produk dinyatakan valid dan layak untuk digunakan. Uji kemenarikan, kemudahan, dan kemanfaatan dilakukan oleh siswa dan diperoleh hasil kemenarikan dengan 3,14, kemudahan dengan skor 3,34 dan kemanfaatan 3,38. Desain penelitian yang digunakan adalah quasi experimental design dalam bentuk nonequivalent pre-post control group design. Berdasarkan hasil uji efektivitas, maka nilai gain kelas eksperimen (0,71) > kelas kontrol (0,45). maka dapat disimpulkan bahwa LKPD dengan pendekatan STEM telah efektif dalam melatih keterampilan berpikir kreatif siswa

The development and evaluation of exercises in meaningful word practice in grade one

Research chapter for this study will be found in Ash, Dorothea: "Development and evaluation of silent reading exercises in grade one" Thesis (Ed.M.)--Boston Universit

The development and evaluation of exercises in meaningful word practice in grade one

Research chapter for this study will be found in Ash, Dorothea: "Development and evaluation of silent reading exercises in grade one" Thesis (Ed.M.)--Boston Universit

Modelling Force-Free Neutron Star Magnetospheres using Physics-Informed Neural Networks

Using Physics-Informed Neural Networks (PINNs) to solve a specific boundary value problem is becoming more popular as an alternative to traditional methods. However, depending on the specific problem, they could be computationally expensive and potentially less accurate. The functionality of PINNs for real-world physical problems can significantly improve if they become more flexible and adaptable. To address this, our work explores the idea of training a PINN for general boundary conditions and source terms expressed through a limited number of coefficients, introduced as additional inputs in the network. Although this process increases the dimensionality and is computationally costly, using the trained network to evaluate new general solutions is much faster. Our results indicate that PINN solutions are relatively accurate, reliable, and well-behaved. We applied this idea to the astrophysical scenario of the magnetic field evolution in the interior of a neutron star connected to a force-free magnetosphere. Solving this problem through a global simulation in the entire domain is expensive due to the elliptic solver's needs for the exterior solution. The computational cost with a PINN was more than an order of magnitude lower than the similar case solved with classical methods. These results pave the way for the future extension to 3D of this (or a similar) problem, where generalised boundary conditions are very costly to implement.Comment: 11 pages, 10 figures, submitted for publication in MNRA

Mixtures of mono-, di- and tri-glycerides as energy supplements to broilers' diets

Mixtures of mono-, di- and tri-glycerides from olive oil (MDT) were added to: palm oil (PO), olive oil (OO), soybean oil (SO), free fatty acids from palm oil (PFA), free fatty acids from olive oil (OFA). The compound mixtures were used as energy supplements in the diets of broiler chickens in comparison with plain SO and plain animal fat (AF). Two hundred and ten birds were randomly allotted to 7 dietary treatments with the diverse oil sources: 6 birds per cage, 5 cages per treatment. The effects of the treatments on growth rates, feed/gain ratios and acidic composition of abdominal fat of hybrid Ross 308 female chickens were studied. The animals were slaughtered at the end of the trial, at day 35. The breast meat quality was then evaluated by a panel of 15 trained members and analysed for shelf life duration. The AF treat- ment gave the highest weight gain, but only in the first week. MDT + OO (50/50) resulted the best combination, with slight, non significant, better performances and a decidedly better quality in terms of acidic composition of abdominal fat, taste and juiciness of breast meat and shelf life

Computation of inflationary cosmological perturbations in chaotic inflationary scenarios using the phase-integral method

The phase-integral approximation devised by Fr\"oman and Fr\"oman, is used for computing cosmological perturbations in the quadratic chaotic inflationary model. The phase-integral formulas for the scalar and tensor power spectra are explicitly obtained up to fifth order of the phase-integral approximation. We show that, the phase integral gives a very good approximation for the shape of the power spectra associated with scalar and tensor perturbations as well as the spectral indices. We find that the accuracy of the phase-integral approximation compares favorably with the numerical results and those obtained using the slow-roll and uniform approximation methods.Comment: 21 pages, RevTex, to appear in Phys. Rev