Ferroelectric Nanotubes

We report the independent invention of ferroelectric nanotubes from groups in several countries. Devices have been made with three different materials: lead zirconate-titanate PbZr1-xTixO3 (PZT); barium titanate BaTiO3; and strontium bismuth tantalate SrBi2Ta2O9 (SBT). Several different deposition techniques have been used successfully, including misted CSD (chemical solution deposition) and pore wetting. Ferroelectric hysteresis and high optical nonlinearity have been demonstrated. The structures are analyzed via SEM, TEM, XRD, AFM (piezo-mode), and SHG. Applications to trenching in Si dynamic random access memories, ink-jet printers, and photonic devices are discussed. Ferroelectric filled pores as small as 20 nm in diameter have been studied

Efficiency of various methods of injection of antituberculosis agents in young patients with destructive pulmonary tuberculosis

The article presents the data of the randomized clinical trial of 80 young patients with destructive pulmonary tuberculosis for various methods of TB drugs injection. Particular attention is paid to the role of parenteral drug delivery. The work demonstrated that newly diagnosed patients with destructive pulmonary tuberculosis of younger age the most optimal and effective is parenteral injection of injectable forms of TB drugs, allowing to halt bacterioexcretion for 3 months in 92.5 % of cases and to close cavities in the lungs in 80 %. In newly diagnosed patients with destructive pulmonary tuberculosis of young age oral use of tablets and of TB drugs is not effective enough, allowing to achieve 3 months cessation of bacterial isolation in 85.2 % of cases and to close cavities in the lungs in 42.5 %. Undesirable side reactions to parenteral administration of injectable forms of TB drugs were detected in 17.5 % of patients and to separate oral tablet forms - in 20 %, fatal reactions were observed in 5 % of cases of drug delivery regardless of method

Features of clinical manifestations and diagnosis of comorbidity of disseminated pulmonary tuberculosis, coronavirus, pneumocystis and pneumococcal pneumonia in patients with late stages of HIV infection with immunodeficiency

Aim. To study the features of clinical manifestations and diagnosis of comorbidity of disseminated pulmonary tuberculosis, coronavirus, pneumocystis and pneumococcal pneumonia in patients with late stages of HIV infection with immunodeficiency. Materials and methods. The prospective study included 120 newly identified patients with disseminated pulmonary tuberculosis with Mycobacterium tuberculosis, stage IVB of HIV infection, in the phase of progression and in the absence of antiretroviral therapy, aged 2953 years, who were randomized into 1A and 2A main groups and 1B and 2B comparison groups. Group 1A included 29 patients with comorbidity and pneumocystis pneumonia and group 2A 31 patients with comorbidity of disseminated pulmonary tuberculosis, coronovirus pneumococcal pneumonia, and group 1B and 2B comprised 29 and 31 similar patients, but without coronovirus pneumonia. To diagnose coronavirus pneumonia, PCR of SARS-CoV-2 RNA was used in smears from the nasopharynx and oropharynx, in sputum or in endotracheal aspirate. To detect Pneumocystis jirovecii, the causative agent of pneumocystis pneumonia, a microscopic examination of diagnostic material from the respiratory tract with RomanovskyGiemse and GrokottGmri coloration was carried out, and to detect Streptococcus pneumoniae, the causative agent of pneumococcal pneumonia, the diagnostic material was seeded on special nutrient media with determination of the drug resistance of the resulting culture to broad-spectrum antibiotics. Statistical data processing was carried out using the Microsoft Office Excel 2019 program with the calculation of the average in the group and the standard error of the average, confidence interval. Results. The comorbidity of disseminated pulmonary tuberculosis, coronavirus, pneumocystis and pneumococcal pneumonia in patients in the late stages of HIV infection, in the phase of progression and in the absence of antiretroviral therapy was characterized by severe immunodeficiency, generalization of tuberculosis with multiple extrapulmonary lesions and severe pneumonia. This determines the similarity of clinical manifestations and respiratory symptoms, and also makes it difficult to visualize computed tomographic changes consisting of a complex simultaneous combination of four pathological syndromes: dissemination, pleural pathology, increased pulmonary pattern and adenopathy. Simultaneous layering of several pathologies with the same type of clinical manifestations and computed tomographic changes requires a comprehensive etiological diagnosis of specific diseases to prescribe timely comprehensive treatment and reduce the lethality of this heavy contingent of patients. Conclusion. Patients with disseminated pulmonary tuberculosis and HIV infection who are registered in the office of tuberculosis care for HIV-infected in the tuberculosis dispensary represent a high risk group of COVID-19 infection and the development of coronavirus pneumonia, and with severe immunodeficiency, pneumocystis and pneumococcal pneumonia, should be regularly subjected to preventive studies for timely detection of COVID-19, coronavirus, pneumocystis and pneumococcal pneumonia for the purpose of their emergency isolation and timely treatment

Ultrafast optical generation of coherent phonons in CdTe1-xSex quantum dots

We report on the impulsive generation of coherent optical phonons in CdTe0.68Se0.32 nanocrystallites embedded in a glass matrix. Pump probe experiments using femtosecond laser pulses were performed by tuning the laser central energy to resonate with the absorption edge of the nanocrystals. We identify two longitudinal optical phonons, one longitudinal acoustic phonon and a fourth mode of a mixed longitudinal-transverse nature. The amplitude of the optical phonons as a function of the laser central energy exhibits a resonance that is well described by a model based on impulsive stimulated Raman scattering. The phases of the coherent phonons reveal coupling between different modes. At low power density excitations, the frequency of the optical coherent phonons deviates from values obtained from spontaneous Raman scattering. This behavior is ascribed to the presence of electronic impurity states which modify the nanocrystal dielectric function and, thereby, the frequency of the infrared-active phonons

Denitration of Radioactive Waste with Formaldehyde During Evaporation in the Natural-Circulation Evaporator

The paper presents a scheme of an experimental full-scale evaporation rig and a description of the tests carried out on it for the evaporation of nitric acid solutions with simultaneous denitration with formaldehyde. The results of work on a full-scale evaporator rig confirmed the possibility of using evaporation method with simultaneous denitration by formaldehyde in a natural-circulation evaporator with external heating chamber. The dependence of concentration of nitric acid to the molar ratio of formaldehyde to nitric acid was obtained. © Published under licence by IOP Publishing Ltd

An approach for the identification of targets specific to bone metastasis using cancer genes interactome and gene ontology analysis

Metastasis is one of the most enigmatic aspects of cancer pathogenesis and is a major cause of cancer-associated mortality. Secondary bone cancer (SBC) is a complex disease caused by metastasis of tumor cells from their primary site and is characterized by intricate interplay of molecular interactions. Identification of targets for multifactorial diseases such as SBC, the most frequent complication of breast and prostate cancers, is a challenge. Towards achieving our aim of identification of targets specific to SBC, we constructed a 'Cancer Genes Network', a representative protein interactome of cancer genes. Using graph theoretical methods, we obtained a set of key genes that are relevant for generic mechanisms of cancers and have a role in biological essentiality. We also compiled a curated dataset of 391 SBC genes from published literature which serves as a basis of ontological correlates of secondary bone cancer. Building on these results, we implement a strategy based on generic cancer genes, SBC genes and gene ontology enrichment method, to obtain a set of targets that are specific to bone metastasis. Through this study, we present an approach for probing one of the major complications in cancers, namely, metastasis. The results on genes that play generic roles in cancer phenotype, obtained by network analysis of 'Cancer Genes Network', have broader implications in understanding the role of molecular regulators in mechanisms of cancers. Specifically, our study provides a set of potential targets that are of ontological and regulatory relevance to secondary bone cancer.Comment: 54 pages (19 pages main text; 11 Figures; 26 pages of supplementary information). Revised after critical reviews. Accepted for Publication in PLoS ON

DC-electric-field-induced and low-frequency electromodulation second-harmonic generation spectroscopy of Si(001)-SiO2_2 interfaces

The mechanism of DC-Electric-Field-Induced Second-Harmonic (EFISH) generation at weakly nonlinear buried Si(001)-SiO$_2$ interfaces is studied experimentally in planar Si(001)-SiO$_2$-Cr MOS structures by optical second-harmonic generation (SHG) spectroscopy with a tunable Ti:sapphire femtosecond laser. The spectral dependence of the EFISH contribution near the direct two-photon $E_1$ transition of silicon is extracted. A systematic phenomenological model of the EFISH phenomenon, including a detailed description of the space charge region (SCR) at the semiconductor-dielectric interface in accumulation, depletion, and inversion regimes, has been developed. The influence of surface quantization effects, interface states, charge traps in the oxide layer, doping concentration and oxide thickness on nonlocal screening of the DC-electric field and on breaking of inversion symmetry in the SCR is considered. The model describes EFISH generation in the SCR using a Green function formalism which takes into account all retardation and absorption effects of the fundamental and second harmonic (SH) waves, optical interference between field-dependent and field-independent contributions to the SH field and multiple reflection interference in the SiO$_2$ layer. Good agreement between the phenomenological model and our recent and new EFISH spectroscopic results is demonstrated. Finally, low-frequency electromodulated EFISH is demonstrated as a useful differential spectroscopic technique for studies of the Si-SiO$_2$ interface in silicon-based MOS structures.Comment: 31 pages, 14 figures, 1 table, figures are also available at http://kali.ilc.msu.su/articles/50/efish.ht

Bmp and Nodal Independently Regulate lefty1 Expression to Maintain Unilateral Nodal Activity during Left-Right Axis Specification in Zebrafish

In vertebrates, left-right (LR) axis specification is determined by a ciliated structure in the posterior region of the embryo. Fluid flow in this ciliated structure is responsible for the induction of unilateral left-sided Nodal activity in the lateral plate mesoderm, which in turn regulates organ laterality. Bmp signalling activity has been implied in repressing Nodal expression on the right side, however its mechanism of action has been controversial. In a forward genetic screen for mutations that affect LR patterning, we identified the zebrafish linkspoot (lin) mutant, characterized by cardiac laterality and mild dorsoventral patterning defects. Mapping of the lin mutation revealed an inactivating missense mutation in the Bmp receptor 1aa (bmpr1aa) gene. Embryos with a mutation in lin/bmpr1aa and a novel mutation in its paralogue, bmpr1ab, displayed a variety of dorsoventral and LR patterning defects with increasing severity corresponding with a decrease in bmpr1a dosage. In Bmpr1a-deficient embryos we observed bilateral expression of the Nodal-related gene, spaw, coupled with reduced expression of the Nodal-antagonist lefty1 in the midline. Using genetic models to induce or repress Bmp activity in combination with Nodal inhibition or activation, we found that Bmp and Nodal regulate lefty1 expression in the midline independently of each other. Furthermore, we observed that the regulation of lefty1 by Bmp signalling is required for its observed downregulation of Nodal activity in the LPM providing a novel explanation for this phenomenon. From these results we propose a two-step model in which Bmp regulates LR patterning. Prior to the onset of nodal flow and Nodal activation, Bmp is required to induce lefty1 expression in the midline. When nodal flow has been established and Nodal activity is apparent, both Nodal and Bmp independently are required for lefty1 expression to assure unilateral Nodal activation and correct LR patterning

Search for Narrow Diphoton Resonances and for gamma-gamma+W/Z Signatures in p\bar p Collisions at sqrt(s)=1.8 TeV

We present results of searches for diphoton resonances produced both inclusively and also in association with a vector boson (W or Z) using 100 pb^{-1} of p\bar p collisions using the CDF detector. We set upper limits on the product of cross section times branching ratio for both p\bar p\to\gamma\gamma + X and p\bar p\to\gamma\gamma + W/Z. Comparing the inclusive production to the expectations from heavy sgoldstinos we derive limits on the supersymmetry-breaking scale sqrt{F} in the TeV range, depending on the sgoldstino mass and the choice of other parameters. Also, using a NLO prediction for the associated production of a Higgs boson with a W or Z boson, we set an upper limit on the branching ratio for H\to\gamma\gamma. Finally, we set a lower limit on the mass of a `bosophilic' Higgs boson (e.g. one which couples only to \gamma, W, and Z$ bosons with standard model couplings) of 82 GeV/c^2 at 95% confidence level.Comment: 30 pages, 11 figure

Measurement of the Strong Coupling Constant from Inclusive Jet Production at the Tevatron pˉp\bar pp Collider

We report a measurement of the strong coupling constant, $\alpha_s(M_Z)$, extracted from inclusive jet production in $p\bar{p}$ collisions at $\sqrt{s}=$1800 GeV. The QCD prediction for the evolution of $\alpha_s$ with jet transverse energy $E_T$ is tested over the range 40<$E_T$<450 GeV using $E_T$ for the renormalization scale. The data show good agreement with QCD in the region below 250 GeV. In the text we discuss the data-theory comparison in the region from 250 to 450 GeV. The value of $\alpha_s$ at the mass of the $Z^0$ boson averaged over the range 40<$E_T$<250 GeV is found to be $\alpha_s(M_{Z})= 0.1178 \pm 0.0001{(\rm stat)}^{+0.0081}_{-0.0095}{\rm (exp. syst)}$. The associated theoretical uncertainties are mainly due to the choice of renormalization scale (^{+6%}_{-4%}) and input parton distribution functions (5%).Comment: 7 pages, 3 figures, using RevTeX. Submitted to Physical Review Letter