Elliptic operators on manifolds with singularities and K-homology

It is well known that elliptic operators on a smooth compact manifold are classified by K-homology. We prove that a similar classification is also valid for manifolds with simplest singularities: isolated conical points and fibered boundary. The main ingredients of the proof of these results are: an analog of the Atiyah-Singer difference construction in the noncommutative case and an analog of Poincare isomorphism in K-theory for our singular manifolds. As applications we give a formula in topological terms for the obstruction to Fredholm problems on manifolds with singularities and a formula for K-groups of algebras of pseudodifferential operators.Comment: revised version; 25 pages; section with applications expande

Proposal for photoacoustic ultrasonic generator based on Tamm plasmon structures

The scheme of generation of ultrasound waves based on optically excited Tamm plasmon structures is proposed. It is shown that Tamm plasmon structures can provide total absorption of a laser pulse with arbitrary wavelength in a metallic layer providing the possibility of the use of an infrared semiconductor laser for the excitation of ultrasound waves. Laser pulse absorption, heat transfer and dynamical properties of the structure are modeled, and the optimal design of the structure is found. It is demonstrated that the Tamm plasmon-based photoacoustic generator can emit ultrasound waves in the frequency band up to 100 MHz with pre-defined frequency spectrum. Optical power to sound power conversion efficiency grows linearly with frequency of the laser modulation and excitation power

Defect properties of solar cells with layers of GaP based dilute nitrides grown by molecular beam epitaxy

International audienceDilute nitrides lattice-matched to GaP were studied to explore the possibilities to improve their properties by additional indium or arsenic content in the GaPN alloy for further utilization in solar cells. Admittance spectroscopy shows that intrinsic layers of GaPNAs and InP/GaPN grown by molecular-beam epitaxy have unintentional background silicon donor doping. Deep-level transient spectroscopy allowed us to reveal several defect levels. In GaPNAs, two defect levels were detected at Ec − 0.58 eV and Ev + 0.44 eV, with respective concentrations of 4 × 1015 cm−3 and 2 × 1015 cm−3. After thermal annealing, these could be reduced by a factor of two and by more than one order of magnitude, respectively, leading to an increase of external quantum efficiency and open-circuit voltage of solar cells. The InP/GaPN layer exhibits a defect level at Ec − 0.44 eV (with a concentration of 2 × 1014 cm−3), which is of similar nature as the one at Ec − 0.58 eV in GaPNAs. Furthermore, unlike in GaPNAs, defect levels close to midgap were also detected in the InP/GaPN layer. These non-radiative recombination centers lead to poorer photoelectric properties of solar cells based on InP/GaPN as compared to those based on GaPNAs. Therefore, the introduction of arsenic in the compound and post-growth thermal annealing allowed us to reduce the defect concentrations in dilute nitrides and improve photoelectrical properties for photovoltaic applications

3D printing of mineral–polymer bone substitutes based on sodium alginate and calcium phosphate

We demonstrate a relatively simple route for three-dimensional (3D) printing of complex-shaped biocompatible structures based on sodium alginate and calcium phosphate (CP) for bone tissue engineering. The fabrication of 3D composite structures was performed through the synthesis of inorganic particles within a biopolymer macromolecular network during 3D printing process. The formation of a new CP phase was studied through X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. Both the phase composition and the diameter of the CP particles depend on the concentration of a liquid component (i.e., the “ink”). The 3D printed structures were fabricated and found to have large interconnected porous systems (mean diameter ≈800 μm) and were found to possess compressive strengths from 0.45 to 1.0 MPa. This new approach can be effectively applied for fabrication of biocompatible scaffolds for bone tissue engineering constructions

FIGURE 33 in On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae)

FIGURE 33. Distribution map of Isochlora spp. in the Tien Shan Massif and Mongolian Altai.Published as part of <i>Volynkin, Anton V., Titov, Sergey V., Matov, Alexey Yu., Tóth, Balázs, Saldaitis, Aidas, Rakhimov, Ruslan D. & Egorov, Petr V., 2023, On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae), pp. 409-423 in Zootaxa 5374 (3)</i> on page 421, DOI: 10.11646/zootaxa.5374.3.5, <a href="http://zenodo.org/record/10152641">http://zenodo.org/record/10152641</a&gt

FIGURES 24–27 in On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae)

FIGURES 24–27. Isochlora spp.: male genitalia. Depositories of the specimens dissected: 24, 26 and 27 in ZISP; 25 in MfN.Published as part of <i>Volynkin, Anton V., Titov, Sergey V., Matov, Alexey Yu., Tóth, Balázs, Saldaitis, Aidas, Rakhimov, Ruslan D. & Egorov, Petr V., 2023, On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae), pp. 409-423 in Zootaxa 5374 (3)</i> on page 419, DOI: 10.11646/zootaxa.5374.3.5, <a href="http://zenodo.org/record/10152641">http://zenodo.org/record/10152641</a&gt

FIGURES 13–19 in On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae)

FIGURES 13–19. Isochlora spp.: adults. The specimens are deposited in ZISP.Published as part of <i>Volynkin, Anton V., Titov, Sergey V., Matov, Alexey Yu., Tóth, Balázs, Saldaitis, Aidas, Rakhimov, Ruslan D. & Egorov, Petr V., 2023, On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae), pp. 409-423 in Zootaxa 5374 (3)</i> on page 416, DOI: 10.11646/zootaxa.5374.3.5, <a href="http://zenodo.org/record/10152641">http://zenodo.org/record/10152641</a&gt

FIGURES 20–23 in On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae)

FIGURES 20–23. Isochlora spp.: male genitalia. Depositories of the specimens dissected: 20 and 21 in MfN; 22 in MH/ HNHM; 23 in ZISP.Published as part of <i>Volynkin, Anton V., Titov, Sergey V., Matov, Alexey Yu., Tóth, Balázs, Saldaitis, Aidas, Rakhimov, Ruslan D. & Egorov, Petr V., 2023, On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae), pp. 409-423 in Zootaxa 5374 (3)</i> on page 418, DOI: 10.11646/zootaxa.5374.3.5, <a href="http://zenodo.org/record/10152641">http://zenodo.org/record/10152641</a&gt

FIGURE 34 in On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae)

FIGURE 34. Distribution map of Isochlora spp. in Qinghai, China.Published as part of <i>Volynkin, Anton V., Titov, Sergey V., Matov, Alexey Yu., Tóth, Balázs, Saldaitis, Aidas, Rakhimov, Ruslan D. & Egorov, Petr V., 2023, On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae), pp. 409-423 in Zootaxa 5374 (3)</i> on page 421, DOI: 10.11646/zootaxa.5374.3.5, <a href="http://zenodo.org/record/10152641">http://zenodo.org/record/10152641</a&gt

FIGURES 1–8 in On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae)

FIGURES 1–8. Isochlora spp.: adults. Depositories of the specimens: 1 and 2 in MfN; 3 in MH/HNHM; 4–6 and 8 in ZISP; 7 in CAV.Published as part of <i>Volynkin, Anton V., Titov, Sergey V., Matov, Alexey Yu., Tóth, Balázs, Saldaitis, Aidas, Rakhimov, Ruslan D. & Egorov, Petr V., 2023, On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae), pp. 409-423 in Zootaxa 5374 (3)</i> on page 412, DOI: 10.11646/zootaxa.5374.3.5, <a href="http://zenodo.org/record/10152641">http://zenodo.org/record/10152641</a&gt