Measurement of the Pion Form Factor with CMD-3 Detector and Its Implication to the Hadronic Contribution to Muon (g-2).

The cross section of the process e^{+}e^{-}→π^{+}π^{-} has been measured in the center-of-mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The measurement is based on an integrated luminosity of about 88 pb^{-1}, of which 62 pb^{-1} represent a complete dataset collected by CMD-3 at center-of-mass energies below 1 GeV. In the dominant region near the ρ resonance a systematic uncertainty of 0.7% was achieved. The implications of the presented results for the evaluation of the hadronic contribution to the anomalous magnetic moment of the muon are discussed.

Programmable quantum emitter formation in silicon.

Silicon-based quantum emitters are candidates for large-scale qubit integration due to their single-photon emission properties and potential for spin-photon interfaces with long spin coherence times. Here, we demonstrate local writing and erasing of selected light-emitting defects using femtosecond laser pulses in combination with hydrogen-based defect activation and passivation at a single center level. By choosing forming gas (N2/H2) during thermal annealing of carbon-implanted silicon, we can select the formation of a series of hydrogen and carbon-related quantum emitters, including T and Ci centers while passivating the more common G-centers. The Ci center is a telecom S-band emitter with promising optical and spin properties that consists of a single interstitial carbon atom in the silicon lattice. Density functional theory calculations show that the Ci center brightness is enhanced by several orders of magnitude in the presence of hydrogen. Fs-laser pulses locally affect the passivation or activation of quantum emitters with hydrogen for programmable formation of selected quantum emitters.

An experimental platform for investigation of the Zeeman effect in strong magnetic fields.

An experimental platform is developed for the investigation of the Zeeman effect in strong magnetic fields. Mega-Gauss magnetic fields are generated by a 1 MA Zebra pulsed power machine using metal rod loads. A gas jet or CH oil on the load is the source of hydrogen. Excited hydrogen atoms are backlit by black body radiation from the rod load. Hydrogen absorption spectra are recorded with a grating spectrometer and intensified gated CCD camera. The experimental platform enables the observation of the quadratic Zeeman effect in hydrogen gas jets using the spectral shift of the central line in the Zeeman triplet. Other gases can be studied using the gas jet method.

A role of methionines in the functioning of oxidatively modified fibrinogen.

Posttranslational modifications in fibrinogen resulting from induced oxidation or oxidative stress in the organism can have deleterious influence on optimal functioning of fibrinogen, causing a disturbance in assembly and properties of fibrin. The protective mechanism supporting the ability of fibrinogen to function in ROS-generating environment remains completely unexplored. The effects of very low and moderately low HOCl/-OCl concentrations on fibrinogen oxidative modifications, the fibrin network structure as well as the kinetics of both fibrinogen-to-fibrin conversion and fibrin hydrolysis have been explored in the current study. As opposed to 25 Μm, HOCl/-OCl, 10 µM HOCl/-OCl did not affect the functional activity of fibrinogen. It is shown for the first time that a number of Met residues, AαMet476, AαMet517, AαMet584, BßMet367, γMet264, and γMet94, identified in 10 µM HOCl/-OCl fibrinogen by the HPLC-MS/MS method, operate as ROS scavengers, performing an important antioxidant function. In turn, this indicates that the fibrinogen structure is adapted to the detrimental action of ROS. The results obtained in our study provide evidence for a protective mechanism responsible for maintaining the structure and functioning of fibrinogen molecules in the bloodstream under conditions of mild and moderate oxidative stress.

[Ankle replacement for severe post-traumatic deformation of the distal tibia: a case report]. / Endoprotezirovanie golenostopnogo sustava pri lechenii gruboi posttravmaticheskoi deformatsii distal'nogo otdela bol'shebertsovoi kosti. Klinicheskii sluchai.

OBJECTIVE: To evaluate the immediate results of ankle replacement with original prosthesis in a patient with severe post-traumatic deformation of the distal tibia. MATERIAL AND METHODS: When developing the original design of ankle prosthesis, we considered foreign analogues of classical and revision models of ankle prostheses taking into account their shortcomings. In this case, an integrated approach was used. Extensive work has been carried out to select materials for prosthetic components. Experimental work with mesenchymal stromal cells of bone marrow was aimed at testing cytotoxicity and biological compatibility. The staff of the department of designing biomechanical structures of the Research Institute of Bionics and Personalized Medicine of the Samara State Medical University carefully studied the proposed design of endoprosthesis using the Ansys software. After cadaver tests on full-scale models, we performed surgical intervention in a patient with severe post-traumatic deformity of the lower third of the left tibia. RESULTS: Our studies revealed convenience and certain advantages of intraoperative installation of original ankle prosthesis. Along with this, this clinical example indicated come features that must be taken into account in revision ankle replacement to avoid possible postoperative consequences. CONCLUSION: Original ankle prosthesis makes it possible to replace the distal tibia and preserve limb function.

Functional Phenotype of Alveolar Macrophages Features in Rats with Metabolic Syndrome.

Phenotypic characteristics of alveolar macrophages in the bronchoalveolar lavage fluid as well as their ability to acquire the M1 and M2 phenotypes during in vitro culturing with reprogramming factors were studied in rats with modeled diet-induced metabolic syndrome. A decrease in the number of alveolar macrophages with the M1 phenotype was found in animals with metabolic syndrome. The factors of metabolic syndrome do not affect phenotypic plasticity of cells in culture, but under the action of M2 reprogramming factors, the cells demonstrate a wide range of phenotypic plasticity by the CD80 and CD206 markers. The consistently high level of production of IL-6 and IL-10 by macrophages during culturing under different conditions indicates functional rigidity of the cells, which is probably a consequence of in vivo predetermined functional phenotype of these cells against the background of metabolic disorders.

All-silicon quantum light source by embedding an atomic emissive center in a nanophotonic cavity.

Silicon is the most scalable optoelectronic material but has suffered from its inability to generate directly and efficiently classical or quantum light on-chip. Scaling and integration are the most fundamental challenges facing quantum science and technology. We report an all-silicon quantum light source based on a single atomic emissive center embedded in a silicon-based nanophotonic cavity. We observe a more than 30-fold enhancement of luminescence, a near-unity atom-cavity coupling efficiency, and an 8-fold acceleration of the emission from the all-silicon quantum emissive center. Our work opens immediate avenues for large-scale integrated cavity quantum electrodynamics and quantum light-matter interfaces with applications in quantum communication and networking, sensing, imaging, and computing.

[Biomechanics of the first metatarsophalangeal joint after replacement]. / Analiz biomekhaniki pervogo plyusnefalangovogo sustava posle endoprotezirovaniya.

OBJECTIVE: Analysis of biomechanics of the first metatarsophalangeal joint after arthroplasty, interaction between bones and two implants of the first metatarsophalangeal joint using skeletal model of the foot. MATERIAL AND METHODS: We developed anatomically adapted all-ceramic non-coupled endoprosthesis of proximal interphalangeal joint between 2016 and 2021. To create a model of the foot, we used diagnostic computed tomography whose images were applied in 3D sculpting system and computer-aided design system for final geometric modeling of the joint. RESULTS: In dorsal flexion of the first metatarsophalangeal joint under 45° with the presence of implant, cortical bone tissue can withstand a load of up to 40 kg. Cortical bone tissue with implant can withstand a load of up to 305 kg without dorsal flexion. Strength of implant elements made of zirconium ceramics significantly exceeds strength of bone tissue within implant-bone tissue connection. CONCLUSION: Postoperative axial load on the first metatarsophalangeal joint up to 35 kg with maximum dorsal flexion up to 45° is the most appropriate. Higher load and hyperextension over 45° may be followed by postoperative complications such as implant instability, dislocation and periprosthetic fracture.

Intracellular Lipid Levels and Oxidative Stress in Peripheral Blood Mononuclear Cells in Experimental Type 1 Diabetes Mellitus.

Type 1 diabetes mellitus was modeled in Wistar rats by intraperitoneal injection of streptozotocin (25 mg/kg for 5 days), which led to the appearance of the main symptoms of insulin-dependent diabetes. In peripheral blood mononuclear cells isolated by centrifugation on a Ficoll density gradient, the production of ROS and the level of intracellular lipids were evaluated by flow cytofluorimetry. In rats with type 1 diabetes mellitus, an increase in ROS levels in isolated peripheral blood monocytes, but not in the lymphocytic fraction was revealed. Incubation of isolated monocytes in a medium containing 1 mM oleic acid led to a 1.5-fold increase of intracellular lipid levels. After incubation of the lymphocyte fraction in this medium, no differences from the control were revealed. Disorders of carbohydrate and lipid metabolism in type 1 diabetes mellitus leading to an increase of free fatty acids and ROS levels can be detected ex vivo in isolated peripheral blood mononuclear cells.

Hypolypidemic Activity of L-Rhamnopyranosyl-6-O-Methyl-D-Galacturonan, a Polysaccharide Isolated from Birch Leaves (Betula pendula L.).

In male Syrian hamsters fed a synthetic high-fat diet enriched with cholesterol (0.3%), administration of a polysaccharide from birch leaves L-rhamnopyranosyl-6-O-methyl-D-galacturonan (3 g/100 g of diet) resulted in a decrease in total cholesterol levels, mainly due to the LDL fraction, triglycerides, and bile acids in blood serum; the content of triglycerides and cholesterol in the liver also decreased, while excretion of bile acids with feces increased. Thus, the lipid-lowering effect of L-rhamnopyranosyl-6-O-methyl-D-galacturonan is related to its ability to bind bile acids in the intestine and interrupt their enterohepatic circulation.

Anti-Atherosclerotic Action of a New Stimulator of Soluble Guanylate Cyclase in an Experiment.

We studied the effect of an indolinone derivative GRS on the development of experimental atherosclerosis in C57BL/6 mice. Atherosclerosis was modeled by intraperitoneal administration of endothelial lipoprotein lipase inhibitor Kolliphor P 407 micro Geismar over 5 months. GRS was administered orally in a dose of 10 mg/kg once a day throughout the experiment. In 5 months, the levels of total cholesterol, LDL, and triglycerides in blood serum, as well as histological composition of the ascending aorta were studied. In mice with experimental atherosclerosis, we observed pronounced dyslipidemia with an increase in serum cholesterol, LDL, and triglycerides and accumulation of xanthoma cells in the aorta wall. Repeat administration of GRS did not eliminate dyslipidemia, but prevented an increase in the number of xanthoma cells in the aorta wall (p<0.05). The stimulator of soluble guanylate cyclase GRS did not exhibit hypolipidemic activity, but restored impaired endothelial function in the atherosclerosis model and prevented atherosclerotic damage to blood vessels and vascular wall remodeling.

The Effect of Vitamin D3 on Neutrophil Extracellular Trap Formation in High-Glucose Conditions.

NETosis, i.e., the formation of neutrophil extracellular traps (NET), and neutrophil autophagy are important elements in the pathogenesis and the development of complications of type 2 diabetes mellitus (T2DM). Therefore, the search of drugs that can regulate the level of NETosis and autophagy in T2DM is relevant. Here we studied an ex vivo NET formation and neutrophil death in whole blood from healthy subjects upon the addition of glucose up to a high concentration of 15 mM or/and the phorbol ester PMA (phorbol-12-myristate-13-acetate). Their individual and combined action caused neutrophil death and an increase in NET content. It can be hypothesized that this resulted from activation of NETosis and autophagy. It was also shown that this activation of NETosis and autophagy is completely prevented by daily intake of 1000 IU vitamin D3 for 14 days. Therefore, vitamin D3 supplementation can be considered as a preventive measure against the development of T2DM complications.

[Perioperative augmented reality technology in surgical treatment of locally advanced recurrent rectal cancer]. / Perioperatsionnoe primenenie tekhnologii dopolnennoi real'nosti v khirurgicheskom lechenii bol'nogo mestnorasprostranennym lokoregionarnym retsidivom raka pryamoi kishki.

Rectal cancer occupies the leading position among cancers, and incidence of locally advanced recurrences is still high despite comprehensive treatment. Combined resections are usually associated with high perioperative risks. These procedures are technically complex interventions requiring further improvement. Virtual reality technology in surgical treatment of locally advanced rectal cancer recurrence has not been widely discussed. The authors present multidisciplinary construction of the matched topographic-anatomical virtual model and virtual planning of the combined surgical intervention. Intraoperative use of augmented reality allowed specifying topographic and anatomical features of surgical area, level of vascular ligation, localization of tumor fixation points and resection borders. These data ensured safety and quality of resection. Further research of augmented reality technology and improvement of its technical aspects will improve the results of surgical treatment of patients with locally advanced pelvic tumors and recurrences.

High-Entropy Layered Rare Earth Hydroxides.

New high-entropy layered rare earth hydroxides ─ (Y,Eu,Gd,Er,Sm)2(OH)5NO3, (Y,Eu,Gd,Er,Tb)2(OH)5NO3, (Y,Eu,Gd,Er,Yb)2(OH)5NO3, (Y,Eu,Gd,Er,Nd)2(OH)5NO3, and (Y,Eu,Gd,Er,Nd,Sm,Tb)2(OH)5NO3 ─ were obtained using a hydrothermal microwave method. The annealing of layered rare earth hydroxides at 900 °C resulted in the corresponding high-entropy rare earth oxides. Based on inductively coupled plasma atomic emission spectroscopy data, the values for configurational entropy for both rare earth hydroxides and oxides were estimated, confirming the formation of high-entropy compounds. Energy-dispersive X-ray spectroscopy mapping, including mapping in the scanning transmission microscopy mode, showed no signs of chemical segregation and confirmed uniform rare earth elements' distribution both in the particles of high-entropy layered basic nitrates and in the particles of high-entropy oxides. The ratios of rare earth cations in the initial aqueous solutions of mixed nitrates were close to the ratios of cations in the resulting high-entropy layered rare earth basic nitrates and high-entropy rare earth oxides.

Quadratic Zeeman effect in hydrogen at 2-3 MG magnetic fields.

The Zeeman effect is used for measurement of magnetic fields in astrophysical and laboratory plasmas. Magnetic fields in atmospheres of magnetic white dwarf stars are in the range 40 kG-1 GG. The quadratic Zeeman effect results in the additional split and shift of lines for magnetic fields >2 MG. Hydrogen Balmer lines were studied in magnetic fields delivered by a 1 MA pulse power generator. The magnetic field was generated by rod loads 0.8-1 mm in diameter. A droplet of CH oil on the load center was the source of hydrogen. A low ionized oil layer was backlit by blackbody emission from the rod with a temperature of 0.5-0.6 eV. Zeeman splitting of H-alpha and H-beta absorption lines were with a grating spectrometer. A spectral shift of the central component of the triplet indicated the quadratic Zeeman effect in hydrogen lines.

[The use of augmented reality technology in endoscopic removal of a maxillary cyst]. / Primenenie tekhnologii dopolnennoi real'nosti v kachestve navigatsionnoi sistemy pri endovideoassotsiirovannom udalenii kisty verkhnei chelyusti.

This article describes the use of augmented reality technology for the removal of an odontogenic cyst of the upper jaw. By combining the image of computed tomography, anatomical formations and the tip of the endoscope in mixed reality, a navigation system was created for performing cystectomy and resection of the tip of the molar root for a volumetric cyst of the maxillary sinus. For the first time, a system for tracking the position of an endoscope in mixed reality in real time was used.

Compact optical grating compressor.

A novel design of a grating-based optical pulse compressor is proposed. The proposed compressor provides a large group delay dispersion while keeping the compressor linear size small. The design of the proposed compressor is based on a traditional Treacy compressor with a straightforward modification of inserting two lenses between the compressor's gratings. This simple alternation aims to substantially increase group delay dispersion of the compressor or alternatively to decrease the compressor size while maintaining its group delay dispersion. A theoretical description of the enhanced compressor has been developed in the paraxial approximation. A detailed numerical model has been built to calculate the compressor parameters more accurately. These theoretical studies have revealed that the enhanced optical compressor provides a significant increase in the group delay dispersion compared to a standard Treacy compressor.

A closer look at the efficiency calibration of LaBr3(Ce) and NaI(Tl) scintillation detectors using MCNPX for various types of nuclear investigations.

The nuclear spectroscopy method has long been used for advanced studies on nuclear physics. In order to decrease costs and increase the efficiency of nuclear radiation investigations, quick and efficient solutions are required. The purpose of this research was to calculate the whole energy peak efficiency values for a range of gamma-ray energies, from 30.973 keV to 1408 keV, at various source-detector distances using the MCNPX Monte Carlo code, which is extensively used in nuclear medicine, industry, and scientific research. As a result, the modeled detectors' full-energy peak efficiencies were calculated and compared to both experimental data and Monte Carlo simulations. Experiment results and prior studies using Monte Carlo simulations were found to be very consistent with these results. The counting efficiency against source-detector distance is then calculated using the modeled detectors. The data we have show that LaBr3(Ce) has outstanding detection properties. This study's findings might be used to improve the design of detectors for use in wide range of high-tech gamma spectroscopy and nuclear research applications.

Airway Smooth Muscles Contractions in Metabolic Syndrome.

We studied contractile responses of isolated airway smooth muscle segments from rats with metabolic syndrome. Metabolic syndrome was induced in rats by high-fat and high-carbohydrate diet. It was shown that metabolic syndrome was associated with an increase of bronchoconstrictor action of cholinergic receptor activator carbacholine (0.1-100 µM) and a decrease of the dilatory effect of ß2-adrenoreceptor activator salbutamol (0.1-100 µM). The observed effects of agonists are epithelium-dependent. Disorders in contractile activity in the airway smooth muscles were accompanied by bronchial epithelium destruction, immune inflammation in the bronchial wall, muscular and peribronchial adipose tissue hypertrophy.

Insulin Resistance in Experimental Type 1 Diabetes Mellitus.

Experimental type 1 diabetes mellitus (T1DM) was induced in rats by daily intraperitoneal injections of alloxan in a dose of 90 mg/kg for 4 days. For verification of insulin resistance, insulin tolerance test was performed in 2 weeks and the glucose utilization rate constant (KITT) was calculated. The rats demonstrated the main symptoms of T1DM: hypoinsulinemia, hyperglycemia, ketonemia, glucosuria, ketonuria, polydipsia, polyphagia, weight loss, and insulin resistance, as evidenced by a decrease in KITT. The serum content of free fatty acids and triacylglycerols significantly increased. The content of triacylglycerols increased in skeletal muscles and decreased in the liver. A negative linear correlation was found between KITT and triacylglycerol content in muscles. Thus, the development of insulin resistance in experimental T1DM in rats is associated with accumulation of triacylglycerols in skeletal muscles.