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The calculation of the design parameters of a disc mill equipped with a feeder made in the form of a conical hopper is given. For shredders of the disintegrator type, it is very important to ensure the uniformity of loading of the crushed material of the working zone of active impact on particles. In addition, the most important factor is the throughput capacity of all sections of the grinding plant. The throughput should be determined by the design and technological parameters of the working chamber of the mill. Its overload can lead to a blockage of the working chamber, and insufficient throughput will negatively affect the intensity and effectiveness of the impact on the particles of the material. For example, insufficient concentration of particles in the secondary zone of the grinding chamber leads to a decrease in the efficiency of mutual abrasion. The article attempts to determine the design and technological parameters in the loading and accelerating parts of the disk mill. At the same time, it is necessary to coordinate the throughput of the disk spreader and the volumetric flow rate of the material particles flowing from the hopper. In this case, it is advisable to take into account that as a result of a rather high rotational speed and the size of the initial particles, with the wrong height of the radial blade of the spreader, material particles can roll over the radial blades, which leads to a delay of the material in the zone of the spreading disc. Therefore, it is necessary to determine the calculation formulas for finding the required height of the radial blade of the spreading disc, depending on the size of the initial particles. The formula demonstrates that the height of the separating blade depends on the particle size, the speed of rotation of the disks and the distance to the point of meeting of the particle with the radial blade.

Metastasis is one of the leading causes of the recurrence and high mortality of cancer. According to a recent hierarchical model of tumour formation, cancer stem cells (CSCs) are responsible for the occurrence of metastases and cancer relapse. Unfortunately, these cells are believed to have high resistance to conventional treatments. The development of therapies focused on the targeted elimination of cancer stem cells is now viewed as a new and advantageous approach to cancer treatment. Here we present a new material – a hybrid of double-stranded DNA (dsDNA) and hexatungsten iodide octahedral cluster {W6I8}4+ – as an effective agent for the targeted X-ray induced photodynamic therapy (X-PDT) of cancer stem cells. Specifically, our approach was to employ an intrinsic property of CSCs to selectively internalise dsDNA molecules to drag {W6I8}, scintillating and photosensitising moieties, directly into CSCs. The hybrid material has high stability in aqueous media, low cytotoxicity in the absence of irradiation, and significant selective cellular uptake by CSCs. X-Ray irradiation of CSCs incubated with the material resulted in an extremely low growth rate of the solid tumour in model CBA mice.

X-ray-induced photodynamic therapy (X-PDT) has recently evolved into a suitable modality to fight cancer. This technique, which exploits radiosensitizers producing reactive oxygen species, allows for a reduction of the radiation dose needed to eradicate cancer in the frame of the radiotherapy treatment of deep tumors. The use of transition metal complexes able to directly produce singlet oxygen, O2(1Δg), upon X-ray irradiation constitutes a promising route towards the optimization of the radiosensitizer's architecture. In our endeavour to conceive pertinent agents for X-PDT, we designed an octahedral molybdenum cluster complex (Mo6) with iodine inner ligands, and carboxylated apical ligands bearing ethylene oxide organic functions. The sodium salt of this complex is highly soluble in aqueous media and displays red luminescence which is efficiently quenched by oxygen to produce O2(1Δg) in a high quantum yield. Furthermore, due to its high radiodensity, the complex exhibits radioluminescence in aqueous media, with the same spectral features as for photoluminescence, indicating the production of O2(1Δg) upon X-ray irradiation. The uptake of the complex by Hep-2 and MRC-5 cells is negligible during the first hours of incubation, then considerably increases in connection with the hydrolysis of the apical ligands. The complex exhibits low toxicity in vitro and induces a radiotoxic effect, noticeable against cancerous Hep-2 cells but negligible against normal MRC-5 cells, at X-ray doses that do not affect cell viability otherwise. The first evaluation of in vivo toxicity of an Mo6 complex on a mouse model evidences a moderate and delayed toxic effect on kidneys, with an intravenous LD50 value of 390 ± 30 mg kg-1, possibly connected with hydrolysis-induced aggregation of the complex. Overall, this complex displays attractive features as a singlet oxygen radiosensitizer for X-PDT, highlighting the potential of transition metal cluster complexes towards this modality.

Parallel Contributed Talk at the "XIX International Workshop on Neutrino Telescopes" on line - 18-26 February, 2021

The three body pion decays π+→l+νX(l=e,μ), where X is a weakly interacting neutral boson, were searched for using the full data set from the PIENU experiment. An improved limit on Γ(π+→e+νX)/Γ(π+→μ+νμ) in the mass range 0

International audience; In the present work of the PIENU experiment, heavy neutrinos were sought in pion decays \(\pi ^{ + } \to \mu ^{ + }\nu \). No evidence for extra peak was found in the muon kinetic energy spectrum and 90% confidence level upper limits were set on the neutrino mixing matrix \(|U_{\mu i}|^{2}\) in the mass range of 15.7 to 33.8 MeV/c^2, improving an order of magnitude over previous experiments. Current status of lepton universality test is also reported.

In the present work of the PIENU experiment, heavy neutrinos were sought in pion decays pi(+) -> mu(+)nu at rest by examining the observed muon energy spectrum for extra peaks in addition to the expected peak for a light neutrino. No evidence for heavy neutrinos was observed. Upper limits were set on the neutrino mixing matrix vertical bar U-mu i vertical bar(2) in the neutrino mass region of 15.7-33.8 MeV/c(2), improving on previous results by an order of magnitude. (C) 2019 The Authors. Published by Elsevier B.V.

A search for massive neutrinos has been made in the decay π+→e+ν. No evidence was found for extra peaks in the positron energy spectrum indicative of pion decays involving massive neutrinos (π→e+νh). Upper limits (90% C.L.) on the neutrino mixing matrix element |Uei|2 in the neutrino mass region 60–135 MeV/c2 were set and are an order of magnitude improvement over previous results.

The PIENU experiment at TRIUMF is aimed at a measurement of the branching ratio R e / μ = Γ ( ( π + → e + ν e ) + ( π + → e + ν e γ ) ) / Γ ( ( π + → μ + ν μ ) + ( π + → μ + ν μ γ ) ) with precision 0.1 % . Incident pions, delivered at the rate of 60 kHz with momentum 75 MeV/c, were degraded and stopped in a plastic scintillator target. Pions and their decay product positrons were detected with plastic scintillators and tracked with multiwire proportional chambers and silicon strip detectors. The energies of the positrons were measured in a spectrometer consisting of a large NaI(Tl) crystal surrounded by an array of pure CsI crystals. This paper provides a description of the PIENU experimental apparatus and its performance in pursuit of R e / μ .

The PIENU experiment at TRIUMF aims to measure the branching ratio of the pion decay modes $R^{\pi}=[{\pi}^+{\rightarrow}e^+{\nu}_e({\gamma})]/[{\pi}^+{\rightarrow}{\mu}^+{\nu}_{\mu}({\gamma})]$ with precision of $

The pion branching ratio, $R_{\pi } = \frac { {\Gamma }(\pi ^{+} \rightarrow e^{+} \nu _{e} + \pi ^{+}\rightarrow e^{+} \nu _{e} \gamma )}{\Gamma (\pi ^{+} \rightarrow \mu ^{+} \nu _{\mu } + \pi ^{+} \rightarrow \mu ^{+} \nu _{\mu } \gamma )}$ , provides a sensitive test of lepton universality and constraints on many new physics scenarios. The theoretical uncertainty on the Standard Model prediction of R π is 0.02 %, a factor of twenty smaller than the experimental uncertainty. The analysis of a subset of data taken by the PIENU experiment will be presented. The result, R π = (1.2344 ± 0.0023(s t a t) ± 0.0019(s y s t)) ⋅ 10−4 [1], is consistent with the Standard Model prediction and represents a 0.1 % constraint on lepton non-universality.

The PIENU experiment aims to measure the branching ratio of the charged pion decay with precision of < 0.1 %. This measurement is much sensitive to search for massive neutrinos coupled to electrons in ${\pi }^{+}{\rightarrow }e^{+}{\nu }_{e}$ decay. The initial analysis was completed and the upper limit on the neutrino mixing parameter |U e i |2 in the neutrino mass range of 0 to 55 MeV/c 2 was improved by a factor of 1.5, and the sensitivity for the mass range of 68 to 129 MeV/c 2 was improve by a factor of up to 4.

Closed-end real estate investment fund is currently one of the most popular instruments of collective investments in Russia. In this article, we have designed a factor score method to evaluate the investment attractiveness of closed-end real estate investment funds as the objective of the research. The method differs from others in three elements of attractiveness evaluation: the real estate market, asset management company, and asset portfolio. We suggest evaluating each element by the appropriate factors. In the research, all the factors are grouped and systemized as variable-based and attributebased factors in the three elements of investment attractiveness. The evaluation is based on the expert scores and factor criteria. Results of the research show the differences between preferences of conservative, moderate and aggressive investors when they invest in closed-end investment fund. The desighed method serves for different types of investors to express their attitude to a specific real estate closed-end fund. Keywords-closed-end investment fund; investment attractiveness; real estate market; asset management company; asset portfolio

A new measurement of the branching ratio R_{e/μ}=Γ(π^{+}→e^{+}ν+π^{+}→e^{+}νγ)/Γ(π^{+}→μ^{+}ν+π^{+}→μ^{+}νγ) resulted in R_{e/μ}^{exp}=[1.2344±0.0023(stat)±0.0019(syst)]×10^{-4}. This is in agreement with the standard model prediction and improves the test of electron-muon universality to the level of 0.1%.

A new measurement of the branching ratio R_{e/μ}=Γ(π^{+}→e^{+}ν+π^{+}→e^{+}νγ)/Γ(π^{+}→μ^{+}ν+π^{+}→μ^{+}νγ) resulted in R_{e/μ}^{exp}=[1.2344±0.0023(stat)±0.0019(syst)]×10^{-4}. This is in agreement with the standard model prediction and improves the test of electron-muon universality to the level of 0.1%.

The PIENU experiment at TRIUMF aims to measure the branching ratio of pion decays R = Γ(π(+) → e(+)ν(e) + π(+) → e(+) ν(e)γ)/Γ(π(+)→μ(+)ν(μ) + π(+) → μ(+)ν(μ)γ) with precision

The branching ratio, Re/μ = Γ(π → eν + eνγ)/Γ(π → μν + μνγ), provides a sensitive test of muon-electron universality in weak interactions. The status of the PIENU experiment at TRIUMF, which aims to improve the precision of the Re/μ measurement by a factor of > 5, is presented.

A TRIUMF experiment, PIENU, which aims to measure the branching ratio of pion decays, R = Γ(π→eν+eνγ)/Γ(π→μν+μνγ) to a precision of 0.1% or better is described. Such a measurement provides the best test of electron-muon universality in weak interactions and is sensitive to an effective mass scale of up to 1000 TeV in new physics.

In the article the authors suggest evaluating the level of diversification using Herfindahl-Hirschman index that reflects the economic activity concentration within the certain timespan. The study of the index in dynamics for Berezovsky company town located in Kemerovo region shows the downward tendency in economic activity concentration whereas its factors remain ambiguous. The research concludes that, on the one hand, a low level of investments in diversification projects does not act upon the diversification process, on the other hand, socio-economic targets of diversification does not correlate with economic structural changes. Thus the diversification process has low effectiveness.

The branching ratio of pion decays, R = Γ(π+→e+νe+π+→e+νeγ)Γ(π+→μ+νμ+π+→μ+νμγ is one of the most accurately calculated decay processes involving hadrons and has provided one of the most stringent tests of the hypothesis of electron-muon universality in weak interactions. The current experimental branching ratio Rexp = (1.230±0.004)×10−4 is 40 times less precise than the theoretical prediction RSM = 1.2352(1)10−4. The TRIUMF PIENU experiment aims at measuring the pion branching ratio with a precision improved by at least a factor five.

A high precision measurement of the ultra-rare K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} decay at Fermilab would be one of the most incisive probes of quark flavor physics this decade. Its dramatic reach for uncovering new physics is due to several important factors: (1) The branching ratio is sensitive to most new physics models which extend the Standard Model to solve its considerable problems. (2) The Standard Model predictions for the K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} and K{sub L}{sup 0} {yields} {pi}{sup 0} {nu}{bar {nu}} branching fractions are broadly recognized to be theoretically robust at the 5-10% level. Only a precious few accessible loop-dominated quark processes can be predicted with this level of certainty. (3) The K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} branching fraction is highly suppressed in the Standard Model to the level < 10{sup -10} (

The positron spectrum from the decay ..pi../sup +/..-->..e/sup +/..nu../sub e/ has been examined for evidence of peaks arising from an admixture in the ..nu../sub e/ weak eigenstate of massive neutrinos. Limits on the intensity of such peaks, together with the measured ..pi -->..e..nu.. branching ratio, have been used to derive constraints on the neutrino mixing parameters over the range 4 MeV

Study of rare decays is an important approach for exploring physics beyond the Standard Model (SM). The branching ratio of the helicity suppressed pion decays, R = , is one of the most accurately calculated decay process involving hadrons and has so far provided the most stringent test of the hypothesis of electron-muon universality in weak interactions. The branching ratio has been calculated in the SM to better than 0.01% accuracy to be RSM = 1.2353(1) × 10 . The PIENU experiment at TRIUMF, which started taking physics data in September 2009, aims to reach an accuracy five times better than the previous experiments, so as to confront the theoretical calculation at the level of ±0.1%. If a deviation from the RSM is found, "new physics" beyond the SM, at potentially very high mass scales (up to 1000 TeV), could be revealed. Alternatively, sensitive constraints on hypotheses can be obtained for interactions involving pseudoscalar or scalar interactions. So far, 4 million π+ → e+ νe ue events have been accumulated by PIENU. This paper will outline the physics motivations, describe the apparatus and techniques designed to achieve high precision and present the latest results.