Electromagnetic Interaction of Massive Spin-3 State from String Theory

In the given work we study an interaction of second massive state of an open boson string with the constant electromagnetic field. This state contains massive fields with spins 3 and 1. Using the method of an open string BRST quantization, we receive gauge-invariant lagrangian, describing the electromagnetic interaction of these fields. From the explicit view of transformations and lagrangian it follows that the presence of external constant e/m field leads to the mixing of the given level states. Most likely that the presence of the external field will lead to the mixing of the states at other mass string levels as well.Comment: 17 pages, LaTeX, no figure

Double Parton Scattering Singularity in One-Loop Integrals

We present a detailed study of the double parton scattering (DPS) singularity, which is a specific type of Landau singularity that can occur in certain one-loop graphs in theories with massless particles. A simple formula for the DPS singular part of a four-point diagram with arbitrary internal/external particles is derived in terms of the transverse momentum integral of a product of light cone wavefunctions with tree-level matrix elements. This is used to reproduce and explain some results for DPS singularities in box integrals that have been obtained using traditional loop integration techniques. The formula can be straightforwardly generalised to calculate the DPS singularity in loops with an arbitrary number of external particles. We use the generalised version to explain why the specific MHV and NMHV six-photon amplitudes often studied by the NLO multileg community are not divergent at the DPS singular point, and point out that whilst all NMHV amplitudes are always finite, certain MHV amplitudes do contain a DPS divergence. It is shown that our framework for calculating DPS divergences in loop diagrams is entirely consistent with the `two-parton GPD' framework of Diehl and Schafer for calculating proton-proton DPS cross sections, but is inconsistent with the `double PDF' framework of Snigirev.Comment: 29 pages, 8 figures. Minor corrections and clarifications added. Version accepted for publication in JHE

Effectiveness of Autologous Platelet-Rich Plasma and Stromal Vascular Fraction in Autologous Skin Grafting

Introduction: Despite the medical advances, burns remain a serious challenge and require new and promising treatment options, such as biomedical technologies with a high potential for burn wound treatment. However, high cost and complexity of biotechnologies limit their routine use, but autologous tissues, such as stromal vascular fraction (SVF) and autologous platelet-rich plasma (PRP), overcome these shortcomings.   Objective: To demonstrate a successful case of using a combination of adipose-derived SVF and autologous PRP during autologous skin grafting in a severely burned patient.   Material and methods: We present a successful case of 84-year-old Patient B. treated at Saint Petersburg I. I. Dzhanelidze Research Institute of Emergency Medicine in September-October 2022. He was diagnosed with a 11% (6%) / II-III degree flame burn of the head, neck, trunk, and upper extremities and first-degree inhalation injury. At the first stage, the general condition of the patient was stabilized, and he was prepared for surgery. At the second stage, on day 25 of treatment we performed skin grafting using split-thickness autografts with rare perforations and application of SVF and autologous PRP on a burn wound. We evaluated the treatment effectiveness using planimetry, cytology, and histology.   Results: We observed complete engraftment of the autograft with no lysis or rejection during the first dressing change on day 3 after surgery and complete skin restoration on day 11. Cytologic findings over time showed an active decrease in inflammatory cells and an increase in regenerative cells, indicating successful wound healing. Histology demonstrated formation of normal stratified squamous epithelium with areas of hyperkeratosis and young granulation tissue in the superficial layers of the dermis on day 6.   Conclusions: Our case demonstrated that the combination of SVF and autologous PRP facilitates split-thickness skin autograft engraftment

Power supplies for dual-frequency induction melting of metals

The article discusses the benefits of multi frequency induction melting in the production of synthetic cast iron, structural (electric circuit) principles of dual frequency Power supplies of melting systems. The ways of electric power regulation of low frequency and high frequency components of the current in the inductor sections of furnace are demonstrated, namely power rescheduling at the metal melting stage, alloying stage and recarburizing of synthetic cast iron

Evaluating the effectiveness of combined use of non-thermal atmospheric pressure plasma and frequently-modulated electric field signal in skin wound healing

Background. Scientists around the world are interested in applying physical phenomena to various fields of science. The development of entire areas united by one concept (‘plasma medicine’, etc.) stands as an outstanding example. This study focuses on only two concepts of interest, which are plasma jet and electric field, as far as results of their combined use in clinical practice and in surgery remain understudied. Objective. Experimental evaluation of the effectiveness of physical methods of treatment in skin wound healing. Material and Methods. Animal testing involved 45 small laboratory animals (rats). They were divided into 5 groups of 9 according to methods for experimental wound healing. To generate the plasma jet, a portable generator was used, which is the original development of specialists of the Peter the Great St. Petersburg Polytechnic University. Planimetric and histological measurements were analysed. The antibacterial effectiveness of methods under research was investigated using Staphylococcus aureus 209P, cultivated in vitro on 6- and 12-millimeter discs. Discussion. A combination of non-thermal atmospheric pressure plasma and frequency-modulated electric field signal exhibited the ability to accelerate eschar separation by 52.1% (p < 0.05) and stimulate restorative regeneration by 56% (p < 0.05). Combination of physical methods of treatment demonstrated pronounced antibacterial effect. A histological examination on biopsy sample on the 21st day of observation revealed formed (mature) granulations and large number of newly formed vessels. The cellular composition of epidermal basement membrane showed high level of differentiation. Conclusion. The data obtained suggest that the use of the proposed methods in clinical practice will improve the treatment process of the patients with wounds of different etiology

Raman Scattering:From Structural Biology to Medical Applications

This is a review of relevant Raman spectroscopy (RS) techniques and their use in structural biology, biophysics, cells, and tissues imaging towards development of various medical diagnostic tools, drug design, and other medical applications. Classical and contemporary structural studies of different water-soluble and membrane proteins, DNA, RNA, and their interactions and behavior in different systems were analyzed in terms of applicability of RS techniques and their complementarity to other corresponding methods. We show that RS is a powerful method that links the fundamental structural biology and its medical applications in cancer, cardiovascular, neurodegenerative, atherosclerotic, and other diseases. In particular, the key roles of RS in modern technologies of structure-based drug design are the detection and imaging of membrane protein microcrystals with the help of coherent anti-Stokes Raman scattering (CARS), which would help to further the development of protein structural crystallography and would result in a number of novel high-resolution structures of membrane proteins—drug targets; and, structural studies of photoactive membrane proteins (rhodopsins, photoreceptors, etc.) for the development of new optogenetic tools. Physical background and biomedical applications of spontaneous, stimulated, resonant, and surface- and tip-enhanced RS are also discussed. All of these techniques have been extensively developed during recent several decades. A number of interesting applications of CARS, resonant, and surface-enhanced Raman spectroscopy methods are also discussed

Multiple Parton Interactions in Z+jets production at the LHC. A comparison of factorized and non--factorized double parton distribution functions

We examine the contribution of Multiple Parton Interactions to Z+n-jets production at the LHC, n=2,3,4, where the Z boson is assumed to decay leptonically. We compare the results obtained with the correlated GS09 double parton distribution function with those obtained with two instances of fully factorized single parton distribution functions: MSTW2008LO and CTEQ6LO. It appears quite feasible to measure the MPI contribution to Z+2/3/4 jets already in the first phase of the LHC with a total luminosity of one inverse femtobarn at 7 TeV. If as expected the trigger threshold for single photons is around 80 GeV, Z+2-jets production may well turn out to be more easily observable than the gamma+3-jets channel. The MPI cross section is dominated by relatively soft events with two jets balancing in transverse momentum.Comment: 15 pages, 3 plot