A compact and sustainable electronic module for silicon photomultipliers

This article presents the development of a cost-effective and efficient electronic module for silicon photomultipliers (SiPM). The electronic module combines essential functionalities, such as a high voltage power supply, a preamplifier, and a signal comparator, into a compact circuit. A high voltage power supply with a range of 30 to 140 V provides a stable bias voltage with 0.01 V accuracy for the SiPMs, while a preamplifier with 40 gain and 250 MHz bandwidth enables signal amplification necessary to extract weak signals. The comparator converts an analogue signal (higher than 8 mV) into TTL (transistor-transistor logic), which makes it easy to process and analyze with digital devices such as microcontrollers or make it possible to send signals over long distances by a cable. The module has been tested using an LYSO scintillator and a SiPM called a micropixel avalanche photodiode (MAPD). It provides a more effective and efficient solution for reading out signals from SiPMs in a variety of applications, delivering reliable and accurate results in real-time.Comment: an article, 9 pages, 6 figure

ПЕРСПЕКТИВЫ СОВЕРШЕНСТВОВАНИЯ АРХИТЕКТУРНО-ПЛАНИРОВОЧНОЙ ОРГАНИЗАЦИИ ПОСЕЛЕНИЙ НА ГОРНОМ ЛАНДШАФТЕ ТАДЖИКИСТАНА

The paper considers actual importance of mountain resettlement and prospective aspects pertaining to formation of rural settlements in mountainous regions of Tajikistan. The problem regarding development and improvement of mountainous regions of the Republic is revealed from the point of view of prospective development of the Republic mountain resources. The paper proposes methodology for architecture-planning improvement of rural settlements located on scarp slopes of mountainous relief. Examples of experimental solutions for planning and development of a rural settlement and its components on the areas of mountainous slope are given in the paper.Рассматриваются актуальность проблемы горного расселения и перспективные аспекты формирования сельских поселений в условиях горных районов Таджикистана. Раскрывается проблема освоения и развития горных регионов республики с позиции перспективного освоения горных ресурсов республики. Предлагаются методики совершенствования архитектурно-планировочной организации сельских поселков на крутых склонах горного рельефа. Приводятся примеры экспериментального решения планировки и застройки сельского поселка и его составных элементов на участках горного склона

Scintillation Light Detection with MAPD-3NK and MPPC-S12572-010P Readout

The linearity and energy resolution of two different solid-state photomultipliers (SiPMs) has been studied with reading out the LFS-8 scintillator (3x3x10 mm3). First SiPM (MAPD-3NK) from Zecotek Photonics consists of deeply burned pixels (cells) and has an active area of 3.7x3.7 mm2. The second one (MPPC-S12572-010P) from Hamamatsu has a surface cell structure and an active area of 3x3 mm2. Both SiPMs have the same pixel density of 10000 mm−2. Energy resolution and linearity of the SiPMs has been studied in the energy range of 59.6-1275 keV. It is found that both SiPMs demonstrate good linearity of signal amplitude as a function of the gamma ray energy in the studied energy range. The detector based on the MAPD-3NK provides significantly good energy resolution in comparison to the detector based on the MPPC-S12572-010P

Biological evaluation of a new sodium-potassium silico-phosphate glass for bone regeneration: In vitro and in vivo studies

In vitro and in vivo studies are fundamental steps in the characterization of new im-plantable materials to preliminarily assess their biological response. The present study reports the in vitro and in vivo characterizations of a novel experimental silicate bioactive glass (BG) (47.5 B, 47.5 SiO2-10 Na2O-10 K2O-10 MgO-20 CaO-2.5 P2O5 mol.%). Cytocompatibility tests were perfor-med using human mature osteoblasts (U2OS), human mesenchymal stem cells (hMSCs) and human endothelial cells (EA.hy926). The release of the early osteogenic alkaline phosphatase (ALP) marker suggested strong pro-osteogenic properties, as the amount was comparable between hMSCs cultivated onto BG surface and cells cultivated onto polystyrene control. Similarly, real-time PCR revealed that the osteogenic collagen I gene was overexpressed in cells cultivated onto BG surface without biochemical induction. Acute toxicity tests for the determination of the median lethal dose (LD50 ) al-lowed classifying the analyzed material as a slightly toxic substance with LD50 = 4522 ± 248 mg/kg. A statistically significant difference in bone formation was observed in vivo through comparing the control (untreated) group and the experimental one, proving a clear osteogenic effect induced by the implantation at the defect site. Complete resorption of 47.5 B powder was observed after only 3 months in favor of newly formed tissue, thus confirming the high osteostimulatory potential of 47.5 B glass

Portable neutron/gamma scintillation detector for status monitoring of accelerator-driven neutron source IREN

Accelerator-driven system (ADS) facilities world-wide opens new opportunities for nuclear physics investigations, so that a high flux of neutrons through spallation reactions can be produced at these facilities. It is known that the measurement, continuous monitoring and optimization of the particle accelerator beam intensity are among the most important actions in the operation of such facilities. Considering this point of view, this paper presents a neutron/gamma counter based on a micropixel avalanche photodiode (MAPD) and a plastic scintillator that monitors the status of the accelerator-driven intense resonance neutron source (IREN) facility by measuring the neutron-gamma intensity in the target hall. The electronics of the modular neutron counter has been designed and developed, including a bias voltage source (up to 130 V), a preamplifier (36 gain) and discriminator (>10 mV) circuit. The last product of MAPD (operation voltage- 55 V, PDE- 33 %, total number of pixels- 136900) was used as a photon readout from a plastic scintillator. The sensitive area of MAPD was 3.7*3.7 mm2 and the size of the plastic scintillator 3.7*3.7*30 mm3. The measurement was carried out in the IREN target hall, where it was necessary to monitor not only high neutron fluxes, but also gamma quanta. The experimental results demonstrated a dependence between the count rate of the detector and the frequency of the accelerator, which ranges from 2 to 50 Hz.Comment: 8 pages, 7 figure

In Vivo Evaluation of 3D-Printed Silica-Based Bioactive Glass Scaffolds for Bone Regeneration

Bioactive glasses are often designed as porous implantable templates in which newly-formed bone can grow in three dimensions (3D). This research work aims to investigate the bone regenerative capability of silicate bioactive glass scaffolds produced by robocasting in comparison with powder and granule-like materials (oxide system: 47.5SiO2-10Na2O-10K2O-10MgO-20CaO-2.5P2O5, mol.%). Morphological and compositional analyses performed by scanning electron microscopy (SEM), combined with energy dispersive spectroscopy (EDS) after the bioactivity studies in a simulated body fluid (SBF) confirmed the apatite-forming ability of the scaffolds, which is key to allowing bone-bonding in vivo. The scaffolds exhibited a clear osteogenic effect upon implantation in rabbit femur and underwent gradual resorption followed by ossification. Full resorption in favor of new bone growth was achieved within 6 months. Osseous defect healing was accompanied by the formation of mature bone with abundant osteocytes and bone marrow cells. These in vivo results support the scaffold’s suitability for application in bone tissue engineering and show promise for potential translation to clinical assessment

Biodiversity of helminths in Karakul sheep in the Khorezm Oasis of Uzbekistan

The purpose of the research is to study the helminth fauna and the structure of helminthocenoses of Karakul sheep in the Khorezm Oasis of Uzbekistan.Materials and methods. The material for this study was helminths collected by conventional methods from Karakul sheep from farms of different types in the Khorezm Region. A total of 13 sheep were studied. To identify the dominant helminth infections in sheep, 110 sets of individual organs were examined by the method of partial helminthological dissections. Helminths were collected in slaughterhouses of the Bagat, Kushkupyr, Urgench, Yangiaryk and Shavat Districts of the Khorezm Region. Additionally, the helminths collected from sheep in the Khorezm Region for 2015–2021 were used.Results and discussion. We found that the helminth fauna of Karakul sheep from the Khorezm Oasis was represented by 22 species of the classes Cestoda, Trematoda and Nematoda. Cestodes were represented by 6 species, trematodes by 3 species, and nematodes by 13 species. The faunistic composition of helminths in studied animals was noticeably depleted as compared to other Uzbekistan regions due to natural and ecological conditions of the Khorezm Oasis. The total helminth infection rate in sheep was 100%. The intensity of infection varied depending on the season of the year and the age of sheep and ranged from tens to several thousand specimens. Almost all organs and systems of the animals were found to be ecological niches of the above helminths. Most of helminth species were common to both domesticated and wild ungulates

Assessment of information value of targeted biopsy and endoscopic removal of colorectal polyps

This research is based on histological investigation of targeted biopsy material and resected polyps’ at 354 patients who applied to National Center of Oncology from 2005 to 2010. All patients underwent targeted biopsy at first with subsequent endoscopic polypectomy and 494 polyps were removed and histologically investigated. The most prevalence type was tubular polyp — 212 (43 %) cases. The rest types of polyps were distributed as follow: tubule-villous type — 125 (25.3 %), villous type — 16 (3.2 %), inflammatory type — 28 (5.7 %), hyperplastic type — 40 (8.1 %), hamartoma type — 21 (4.3 %) cases. In 52 (10.4 %) cases malignant polyps were revealed.Sensitivity of targeted biopsy in iagnostics of dysplasia was 65.1 % while in revealing of malignancy was even lower — just 36.5 %. So we consider performing of endoscopic polypectomy and histological evaluation of resected polyps in all case even after previous targeted biopsy