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The influence of the carrier-envelope phase (CEP) of a pump pulse on the multioctave supercontinuum (SC) generation in a gas-filled anti-resonant hollow-core fiber (AR HCF) by soliton self-compression (SSC) has been explored. We have shown an octave-wide third harmonic generation (THG) in the visible-to-near-infrared range during the pulse compression down to a sub-cycle duration. The CEP of a multi-cycle pump pulse provides control of interference between the third harmonic (TH) and the SC that indicates the coherent synthesis of a sub-cycle pulse with a duration of about 0.4 optical cycles and a peak power of more than 2 GW at the fiber output.

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The paper describes the effect of the addition of alumina nanofibers on the mechanical properties of the epoxy resin. Alumina nanofibers functionalized with epoxypropyl functional groups are used in this work. The dependence of the mechanical characteristics on the amount of the additive, as well as the features of its distribution in the material, is investigated. In the work, nanocomposites were obtained, which are epoxy resin with aluminum oxide nanofibers. The mechanical properties of the samples were studied by bending tests and differential mechanical analysis (DMA). It has been shown that the addition of alumina nanofibers leads to an increase in ultimate flexural strength. The maximum of this increase is near the percolation threshold of alumina nanofibers in epoxy resin. With the addition of 0.2% alumina nanofibers, the ultimate flexural strength increases from 41 to 71 MPa. It is shown that after exceeding the percolation threshold of nanofibers, the ultimate strength decreases. In this case, the elastic modulus increases from 0.643 to 0.862 GPa. DMA is shown that the glass transition temperature decreases with increasing amount of the additive. This indicates a decrease in the molecular weight of the polymer. By implication, this suggests that the hardener connects the epoxypropyl functional groups on the nanofibers and the epoxy groups in the resin, and as a result of this process, the nanofibers become natural polymer chain length limiters. The data obtained from mechanical testing and differential mechanical analysis can be used to strengthen epoxy resins in polymer composite materials and molding compositions.

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OBJECTIVE: To evaluate the effectiveness of hybrid interventions, i.e. endovascular mechanical thrombectomy from intracranial arteries combined with open thrombectomy or carotid endarterectomy from extracranial internal carotid artery. MATERIAL AND METHODS: We analyzed 16 patients who underwent mechanical thrombectomy/thrombaspiration combined with open surgery between January 2014 and March 2021. All patients had occlusion of extracranial and intracranial segments internal carotid artery or initial segments of the middle cerebral artery. Baseline data, diagnostic algorithm, timing and results of treatment were analyzed. Study endpoints were technical success of revascularization, clinically significant hemorrhagic transformation, NIHSS and modified Rankin score of neurological impairment, as well as outcome of disease within 90 days. RESULTS: We restored patency of ICA and intracranial arteries in 13 out of 16 patients. In 9 patients, we obtained a positive effect with significant regression of neurological symptoms (mRS <2). In 3 patients, severe neurological deficit persisted throughout the entire follow-up period. Four patients died. Thus, effectiveness of technique was 56.2% (t=3), mortality rate was 25% (t=2.3). There was a relationship between the timing of interventions and outcomes of disease. Indeed, all dead and most of disabled patients underwent surgery later than 6 hours from the onset of disease. CONCLUSION: Hybrid interventions for tandem occlusions of carotid arteries can significantly increase efficiency and accelerate recanalization of great extracranial vessels in patients with tandem lesions in acute phase of ischemic stroke. Moreover, hybrid interventions significantly reduce the cost of reperfusion procedure. In case of severe atherosclerotic stenosis, simultaneous open endarterectomy from common and internal carotid arteries has a significant advantage over stenting due to no need for antithrombotic therapy.

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The objective of the study is to determine the optimal conditions for blood sample preparation by liquid-liquid extraction using mathematical planning of the experiment by the example of forensic chemical study of verapamil. Evaluation of verapamil recovery from blood samples was performed according to the scheme of multivariate three-level experimental planning using the Box-Behnken design. The effect of aqueous phase pH, the ratio of chloroform to n-butanol in the extraction agent, extraction and centrifugation time, addition of sodium chloride, and the ratio of sample and extraction agent volumes on the recovery was studied. The algorithm using mathematical planning and development of liquid-liquid extraction model of target analyte can be recommended for analysis procedure optimization in forensic chemistry.

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AIM: To study the efficiency of the treatment of patients with chronic abacterial prostatitis using the drug Prostatex. MATERIALS AND METHODS: A total of 72 patients aged 22 to 43 years with chronic abacterial prostatitis were included in the study. All patients received Prostatex in the form of suppositories 10 mg QD within 20 days. The duration of the follow-up was 1 month. RESULTS: By the third visit from the start of treatment, there were almost no symptoms of the disease, according to the NIH-CPSI and IPSS questionnaires. In 67 (93.1%) patients, the prostate became an elastic, while in 69 (95.8%) men it was painless at palpation. In addition, a decrease in the prostate size, volume of residual urine and an improvement in urine flow rate were seen. CONCLUSION: Our results showed that monotherapy with Prostatex in patients with chronic abacterial prostatitis was effective and had pathogenetic rationale. This drug has a positive effect on the main symptoms of the disease, significantly reduces pain, urination disturbances, helps to reduce the prostate size and the volume of residual urine, improves prostate microcirculation and can be recommended for this category of patients.

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The objective of this work is to evaluate the possibility of biological fluids sample preparation in forensic toxicology using a molecularly imprinted sorbent based on acrylic acid derivatives. Phenylpiracetam has similar physicochemical properties to those of pyrrolidinophenone derivatives and reproduces their behavior during solid-phase extraction. The phenylpiracetam recovery from blood and urine model samples is 75% for concentration range of 100.0-6000.0 ng/ml. The accuracy of phenylpiracetam extraction does not exceed ±12% for blood samples and ±6% for urine samples. The repeatability is no more than 16% and 13% for blood and urine samples, respectively. A study of the cross-reactivity of the molecularly imprinted sorbent with some drugs showed the selectivity of the sample preparation procedure.

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Spectral analysis of high-order harmonics generated by ultrashort mid-infrared pulses in molecular nitrogen reveals well-resolved signatures of inverse Raman scattering, showing up near the frequencies of prominent vibrational transitions of nitrogen molecules. When tuned on a resonance with the v'=0→v''=0 pathway within the B3Πg→C3Πu second positive system of molecular nitrogen, the eleventh harmonic of a 3.9 µm, 80 fs driver is shown to acquire a distinctive antisymmetric spectral profile with red-shifted bright and blue-shifted dark features as indicators of stimulated Raman gain and loss. This high-harmonic setting extends the inverse Raman effect to a vast class of strong-field light-matter interaction scenarios.

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We theoretically study an impulsively excited quantum bouncer (QB)-a particle bouncing off a surface in the presence of gravity. A pair of time-delayed pulsed excitations is shown to induce a wave-packet echo effect-a partial rephasing of the QB wave function appearing at twice the delay between pulses. In addition, an appropriately chosen observable [here, the population of the ground gravitational quantum state (GQS)] recorded as a function of the delay is shown to contain the transition frequencies between the GQSs, their populations, and partial phase information about the wave-packet quantum amplitudes. The wave-packet echo effect is a promising candidate method for precision studies of GQSs of ultracold neutrons, atoms, and antiatoms confined in closed gravitational traps.

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Experimental and theoretical screening of multi-component crystal forms of miconazole (MCL), an antifungal drug, with ten aliphatic dicarboxylic acids was performed. Seven multi-component molecular crystals were isolated and identified by different analytical techniques, including the powder X-ray diffractometry (PXRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), and solubility methods. The crystal structures of the MCL hemihydrate, two cocrystals with succinic ([MCL + SucAc] (2 : 1)) and fumaric acids ([MCL + FumAc] (2 : 1)) and one salt with maleic acid ([MCL + MleAc] (1 : 1)) were redetermined. The new cocrystal of MCL with adipic acid ([MCL + AdpAc] (2 : 1)) was investigated by single crystal X-ray diffractometry. It was found that the AdpAc molecule in the cocrystal has an unusual anticlinal conformation. The combination of periodic density functional theory (DFT) computations and quantum topology analysis confirmed the structure-directing role of the acid-imidazole heterosynthon for the considered crystals. The melting temperatures of all the studied multi-component crystals are between the values of the corresponding individual components except [MCL + MleAc] (1 : 1). A thermal analysis has shown that the thermodynamic and thermophysical characteristics of the considered two-component molecular crystals are strongly dependent both on specific interactions (presence of sites of donor-acceptor interactions and hydrogen bond formation) and on nonspecific interactions - molecule polarizability. Based on the sublimation thermodynamics database of molecular crystals, the standard sublimation thermodynamic functions of MCL were evaluated. The thermodynamic functions of multi-component crystal formation based on MCL were calculated and analyzed. Solubility experiments on the MCL multi-component crystals were carried out in isotonic aqueous buffer solutions at pH 1.2 and 6.8 and compared with the solubility of the MCL free base and its nitrate salt. It was found that the salt/cocrystal formation of MCL with dicarboxylic acids considerably increased the MCL solubility in pH 6.8 buffer. The biggest MCL solubility enhancement was observed in the [MCL + TartAc] (1 : 1) salt. The solubility value of MCL in the [MCL + TartAc] (1 : 1) salt is commensurate with the commercial MCL nitrate salt.

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Ultrafast ionization of a gas medium driven by ultrashort midinfrared laser pulses provides a source of bright ultrabroadband radiation whose spectrum spans across the entire microwave band, reaching for the sub-gigahertz range. We combine multiple, mutually complementary detection techniques to provide an accurate polarization-resolved characterization of this broadband output as a function of the gas pressure. At low gas pressures, the lowest-frequency part of this output is found to exhibit a drastic enhancement as this field builds up its coherence, developing a well-resolved emission cone, dominated by a radial radiation energy flux. This behavior of the intensity, coherence, and polarization of the microwave output is shown to be consistent with Cherenkov-type radiation by ponderomotively driven plasma currents.

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The aim of the work is to test theoretical prognosis of metrological characteristics of methods of quantitative determination in forensic chemical analysis on the example of method of determination of verapamil content in blood by thin layer chromatography with computer densitometry. The algorithm of prognostic determination of relative error for methods of quantitative analysis in forensic chemical examination using computer program «ChemMetrEvaluation 1.0¼ is offered. The implementation of the algorithm is based on a detailed analysis of error estimation of measurements at the stages of sample preparation, measuring the value of the analytical signal.

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We identify an unusual regime of ultrafast nonlinear dynamics in which an optical shock wave couples to soliton self-compression, steepening the tail of the pulse, thus yielding self-compressing soliton transients as short as the field sub-half-cycle. We demonstrate that this extreme pulse self-compression scenario can help generate sub-half-cycle mid-infrared pulses in a broad class of anomalously dispersive optical waveguide systems.

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Coherent-wake plasma emission induced by ultrashort mid-infrared laser pulses on a solid target is shown to give rise to high-brightness, high-order harmonic radiation, offering a promising source of attosecond pulses and a probe for ultrafast subrelativistic plasma dynamics. With 80-fs, 0.2-TW pulses of 3.9-µm radiation used as a driver, optical harmonics up to the 34th order are detected, with their spectra stretching from the mid-infrared region to the extreme ultraviolet region. The harmonic spectrum is found to be highly sensitive to the chirp of the driver. Particle-in-cell analysis of this effect suggests, in agreement with the generic scenario of coherent-wake emission, that optical harmonics are radiated as trains of extremely short, attosecond ultraviolet pulses with a pulse-to-pulse interval varying over the pulse train. A positive chirp of the driver pulse can partially compensate for this variation in the interpulse separation, allowing harmonics of the highest orders to be generated in the plasma emission spectrum.

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The article the literature review on dental materials for the manufacture of gum formers used in dental implantology. Adhesion of microorganisms to titanium, PMMA and PEEK resins is discussed. According to published studies PEEK polymer is characterized by a similar bacterial contamination compared to titanium but shows lower degree of contamination when compared to acrylic resins in equal conditions.

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The purpose of the work is the development of mathematical models in the forensic diagnosis of poisonings by the main groups of toxicologically important substances, on the basis of biochemical characteristics of blood. The most informative forensic and biochemical indicators of cadaveric blood used to detect lethal poisoning are the urea content, total protein content, and the ratio of urea to creatinine. Mathematical models of poisoning can be used to diagnose poisoning with narcotic drugs, psychotropic substances and substitutes of ethyl alcohol.

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An observation of neutron-antineutron oscillations (n-n[over ¯]), which violate both B and B-L conservation, would constitute a scientific discovery of fundamental importance to physics and cosmology. A stringent upper bound on its transition rate would make an important contribution to our understanding of the baryon asymmetry of the Universe by eliminating the postsphaleron baryogenesis scenario in the light quark sector. We show that one can design an experiment using slow neutrons that in principle can reach the required sensitivity of τ_{n-n[over ¯]}∼10^{10} s in the oscillation time, an improvement of ∼10^{4} in the oscillation probability relative to the existing limit for free neutrons. The improved statistical accuracy needed to reach this sensitivity can be achieved by allowing both the neutron and antineutron components of the developing superposition state to coherently reflect from mirrors. We present a quantitative analysis of this scenario and show that, for sufficiently small transverse momenta of n/n[over ¯] and for certain choices of nuclei for the n/n[over ¯] guide material, the relative phase shift of the n and n[over ¯] components upon reflection and the n[over ¯] annihilation rate can be small enough to maintain sufficient coherence to benefit from the greater phase space acceptance the mirror provides.

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Analysis of the complex refractive index of atmospheric air reveals remarkably broad and continuous regions of anomalous and near-zero group-velocity dispersion in the subterahertz (sub-THz) and millimeter-band atmospheric windows. One such broadband dispersion anomaly is shown to occur in the high-frequency wing of the 60-GHz band of molecular oxygen. Adjacent to this dispersion anomaly is a broadband atmospheric transparency region within which the group-velocity dispersion is unusually weak, enabling distortion-free long-distance transmission of broadband millimeter-wave field waveforms, as well as broadband remote sensing in the millimeter band. Although broad regions of anomalous and near-zero dispersion also exist in the sub-THz range, their utility for long-distance transmission and remote sensing is limited because of strong atmospheric absorption.

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Formation of light bullets-tightly localized in space and time light packets, retaining their spatiotemporal shape during propagation-is, for the first time, experimentally observed and investigated in a new regime of mid-infrared filamentation in ambient air. It is suggested that the light bullets generated in ambient air by multi-mJ, positively chirped 3.9-µm pulses originate from a dynamic interplay between the anomalous dispersion in the vicinity of CO2 resonance and positive chirp, both intrinsic, carried by the driver pulse, and accumulated, originating from nonlinear propagation in air. By adjusting the initial chirp of the driving pulses, one can control the spatial beam profile, energy losses, and spectral-temporal dynamics of filamenting pulses and deliver sub-3-cycle mid-IR pulses in high-quality beam on a remote target.

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High-order harmonic generation (HHG) in plasmas induced by ultrashort, relativistic-intensity laser pulses on solid surfaces can provide an efficient source of attosecond pulses and opens routes toward new regimes of laser-matter interactions, x-ray generation, laser particle acceleration, and relativistic nonlinear optics. However, field intensities in the range of Irel∼1019 W/cm2 are typically needed to achieve the relativistic regime of HHG in experiments with near-infrared laser pulses. Here, we show that, in the mid-infrared range, due to the λ-2 scaling of Irel with the driver wavelength λ, relativistic HHG can be observed at much lower levels of laser field intensities. High-peak-power 80-fs, 3.9-µm pulses are focused in our experiments on a solid surface to provide field intensities in the range of 1017 W/cm2. Remarkably, this level of field intensities, considered as low by the standards of relativistic optics in the near infrared, is shown to be sufficient for generation of high-order harmonics with signature properties of relativistic HHG-beam directionality, spectra with extended plateaus, and a high HHG yield sustained for both p- and s-polarized driver fields.

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Properties of filaments ignited by multi-millijoule, 90 fs mid-infrared pulses centered at 3.9 µm are examined experimentally by monitoring plasma density, losses, spectral dynamics and beam profile evolution at different focusing strengths. By changing from strong (f=0.25 m) to loose (f=7 m) focusing, we observe a shift from plasma-assisted filamentation to filaments with low plasma density. In the latter case, filamentation manifests itself by beam self-symmetrization and spatial self-channeling. Spectral dynamics in the case of loose focusing is dominated by the nonlinear Raman frequency downshift, which leads to the overlap with the CO2 resonance in the vicinity of 4.2 µm. The dynamic CO2 absorption in the case of 3.9 µm filaments with their low plasma content is the main mechanism of energy losses and, either alone or together with other nonlinear processes, contributes to the arrest of intensity.