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The possibility of frequency stabilization of two gyrotrons with similar parameters when part of their radiation is reflected from the common external high-Q resonator is demonstrated analytically. In stabilized regime, the frequencies of both gyrotrons are equal and change slightly when the eigenfrequencies of the gyrotron cavities change. The study is based on the equations of coupled oscillations of gyrotrons and an external resonator. The stability of equilibrium states has been researched. The permissible difference in the autonomous generation frequencies of gyrotrons has been found, at which stabilization of their frequency is possible. The analytical results are confirmed by numerical simulation using the example of gyrotrons with a megawatt power level and an operating frequency of 170 GHz. [ABSTRACT FROM AUTHOR]

The transboundary transport of pollution by channel water flows causes environmental–economic losses in territories located in the lower reaches of rivers. In this case, very serious problems arise not only in the streams that cross state borders, but also on the borders between entities of the same country. The first problem is the reliability of water quality estimate against the background of considerable instability of hydrological regime and based on existing monitoring systems. This problem is considered in the case of the transboundary Ural River. An algorithm is proposed for the formation of a constructive dialogue between interested parties by taking into account the statistical characteristics of the measurement results obtained at neighboring sites of hydrochemical observations. It is shown that in this case a threshold of distinguishability of the controlled indicators should be taken into account and the errors of the 1st and 2nd kind are to be regulated. It is demonstrated that economic losses that result from the lack of constructive relations between the parties regarding the estimation of the controlled indicators can be determined. [ABSTRACT FROM AUTHOR]

A millimeter wave interferometer based on a Ka-band CW signal generator and a high-speed oscilloscope has been implemented, which makes it possible to carry out measurements without frequency conversion. The experimental measurements of the amplitude of transverse deformations of a metal rod caused by impact loading have been carried out. A good agreement between the calculated and measured data was revealed, demonstrating the possibility to measure microsecond-duration surface deviations with an accuracy of about 1 μm and a relative error of about 8%. [ABSTRACT FROM AUTHOR]

Tyrosine kinase inhibitors (TKIs) have greatly improved chronic myeloid leukemia (CML) treatments, with survival rates close to the general population. Yet, for the very elderly, robust data remains limited. This study focused on assessing comorbidities, treatment approaches, responses, and survival for elderly CML patients. Our study was conducted on 123 elderly (≥ 75 years) CML patients across four centers in Israel and Moffitt Cancer Center, USA. The median age at diagnosis was 79.1 years, with 44.7% being octogenarians. Comorbidities were very common; cardiovascular risk factors (60%), cardiovascular diseases (42%), with a median age-adjusted Charlson Comorbidity Index (aaCCI) of 5. Imatinib was the leading first-line therapy (69%), while the use of second-generation TKIs increased post-2010. Most patients achieved a major molecular response (MMR, 66.7%), and half achieved a deep molecular response (DMR, 50.4%). Over half (52.8%) of patients moved to second-line, and nearly a quarter (23.5%) to third-line treatments, primarily due to intolerance. Overall survival (OS) was notably longer in patients with an aaCCI score below 5, and in patients who attained DMR. Contrary to expectations, the Israeli cohort showed a shorter actual life expectancy than projected, suggesting a larger impact of CML on elderly survival. In summary, imatinib remains the main initial treatment, but second-generation TKIs are on the rise among elderly CML patients. Outcomes in elderly CML patients depend on comorbidities, TKI type, response, and age, underscoring the need for personalized therapy and additional research on TKI effectiveness and safety. [ABSTRACT FROM AUTHOR]

Background: Psychological interventions are commonly applied in sports to help athletes enhance their performance, but the effect psychological interventions have on actual performance is unclear despite decades of research. Objective: We conducted a systematic review with meta-analyses to investigate the effects of a wide range of psychological interventions on performance in competitive athletes. Methods: A study protocol was preregistered in PROSPERO, and a literary search was performed in the MEDLINE, PsycINFO, Web of Science, and SPORTDiscus databases. Psychological intervention studies were eligible by using a group design and a quantitative performance outcome with athletes competing at a regional or university level or higher. Included studies were assessed regarding intervention characteristics, research methodology, and risk of bias. A multi-level meta-analysis framework with cluster robust variance estimation was used to quantitatively synthesize the results. Results: A total of 111 studies met the inclusion criteria, and 25 of these studies (37 effects) could be synthesized into five meta-analyses in which there were similarities in the type of psychological intervention, comparator, and experimental design. Meta-analyses I (multimodal psychological skills training vs control), II (mindfulness- and acceptance-based approaches vs control), and III (imagery vs control) consisted of parallel-group studies, and random-effects models were used to calculate the standardized mean difference. Meta-analyses IV (attentional focus strategies, external vs internal) and V (regulatory focus performance instructions, prevention vs promotion) consisted of counterbalanced crossover design studies, and random-effects models were used to calculate the standardized mean change using change score standardization. Significant results were found in three of the meta-analyses (I, II, and III). Psychological skills training (g = 0.83, 95% confidence interval 0.21–1.45), mindfulness- and acceptance-based approaches (g = 0.67, 95% confidence interval 0.01–1.32), and imagery (g = 0.75, 95% confidence interval 0.14–1.36) outperformed controls with moderate effects. However, when non-randomized trials and subjective performance outcomes were removed in sensitivity analyses, the overall estimates of the effect size were no longer significant in any of the syntheses. Conclusions: The significant moderate effects for psychological skills training, mindfulness- and acceptance-based approaches, and imagery are not stable, and further trials with robust research methodology, such as randomized controlled trials, are requested for all types of psychological interventions aiming to enhance performance in athletes. Moreover, improved reporting standards and the provision of datasets in open science repositories are important to consider in future trials in sport psychology. Clinical Trial Registration: PROSPERO CRD42017056677. [ABSTRACT FROM AUTHOR]

Calculations are made for a three-electrode magnetron-injector gun with a thermionic cathode for a relativistic gyrotron in the 300 GHz range. The gyrotron allows the formation of a helical beam with an energy of 250 keV, a current of 100–300 A, and a pitch factor of 1.1. The possibility of generating radiation with power of more than 8 MW in a gyrotron with a longitudinally slotted cavity is shown via three-dimensional PIC modeling. [ABSTRACT FROM AUTHOR]

Theoretical and experimental studies are performed of the generation of radiation in the mode of frequency multiplication at the third harmonic in a high-current Ka-band gyrotron. Three-dimensional PIC modeling shows that the coefficient of nonlinear transformation in the W-band can reach values of 0.5%. Experimental data are presented on recording radiation in this range. [ABSTRACT FROM AUTHOR]

We consider the possibilities of producing wideband chaotic terahertz-range radiation in gyrotrons with excitation of cyclotron harmonics. The transition to the chaotic generation mode in gyrotrons requires a significant excess of the operating current over the starting value, which excludes selective operation at cyclotron harmonics due to the intensification of mode competition. At the same time, it is attractive to use a competition-free frequency multiplication effect that arises due to the nonlinear properties of the electron beam. The implementation of the frequency multiplication regime is simplified when using low-energy electron beams. Based on the averaged model of electron-wave interaction, we simulate generation in a 250-GHz low-voltage gyrotron and demonstrate the regime of a double frequency multiplication providing 0.5 THz chaotic radiation with a bandwidth of about 20 GHz and an average power of 0.5 mW. A significant expansion of the spectrum is achieved through to additional resonant interaction at the intersection points of the dispersion characteristics of the operating mode and the electron beam at the second cyclotron harmonic. [ABSTRACT FROM AUTHOR]

We develop and study for the first time a high-current Ka-band gyrotron having an electron-optical system with magnetic compression, which ensures the formation of a helical electronc beam with an energy of 500 keV, a current of 2 kA, and a pitch factor of about 1.0. Generation of the radiation with a power of 35–40 MW and a pulse duration of about 5 ns is achieved at the TE−3, 2 and TE−4, 2 modes with frequencies of 30.6 and 35.7 GHz, respectively. [ABSTRACT FROM AUTHOR]

We compare two methods of millimeter radio interferometry with and without frequency conversion using as an example experimental measurements of the transverse deformation magnitude of a metal rod under dynamic load. We reveal a good agreement between the results, demonstrating a possibility of measuring the surface deviations within times of about 1 μs with micron precision. [ABSTRACT FROM AUTHOR]

Calculations are presented for an electron-optical system that makes it possible to produce a helical electron beam with an energy of 250 keV, a current of 100 A, and a pitch factor of 1.1 for a 0.3 THz gyrotron with the operating mode of TE33.2. Based on averaged stationary equations with a non-fixed field structure, the cavity profile is optimized and the possibility of obtaining an output power of about 8 MW with an electronic efficiency of more than 30% is demonstrated. Within the framework of particle-in-cell three-dimensional simulation, the processes of establishing oscillations are considered. Besides, it is shown that in the range of magnetic fields from 14.7 to 15.1 T, selective excitation of oscillations in the operating mode with a maximum power of about 7 MW is possible. [ABSTRACT FROM AUTHOR]

The subclass naphthoquinone represents a substance group containing several compounds with important activities against various pathogenic microorganisms. Accordingly, we evaluated O-allyl-lawsone (OAL) antiparasitic and antifungal activity free and encapsulated in 2-hydroxypropyl-β-cyclodextrin (OAL MKN) against Trypanosoma cruzi and Sporothrix spp. OAL and OAL MKN were synthesized and characterized by physicochemical methods. The IC50 values of OAL against T. cruzi were 2.4 µM and 96.8 µM, considering epimastigotes and trypomastigotes, respectively. At the same time, OAL MKN exhibited a lower IC50 value (0.5 µM) for both trypanosome forms and low toxicity for mammalian cells. Additionally, the encapsulation showed a selectivity index approximately 240 times higher than that of benznidazole. Regarding antifungal activity, OAL and OAL MKN inhibited Sporothrix brasiliensis growth at 16 µM, while Sporothrix schenckii was inhibited at 32 µM. OAL MKN also exhibited higher selectivity toward fungus than mammalian cells. In conclusion, we described the encapsulation of O-allyl-lawsone in 2-hydroxypropyl-β-cyclodextrin, increasing the antiparasitic activity compared with the free form and reducing the cytotoxicity and increasing the selectivity towardSporothrix yeasts and the T. cruzi trypomastigote form. This study highlights the potential development of this inclusion complex as an antiparasitic and antifungal agent to treat neglected diseases. [ABSTRACT FROM AUTHOR]

The article considers neural-network methods and technologies, which are relatively new even for many researchers and experts, as applied to water–environmental regulation. The efficiency of neural networks in this line of studies is due to their self-training, and the ensuing ability to reveal complex nonlinear relationships between the characteristics under control by data processing instruments, consisting of interrelated neurons. The methodology of artificial neural networks and the features of their functioning are described. Training and methodological examples are given to illustrate their potential use. A practical problem, considered as an example of ANN application, is the potential for improving the efficiency of identification of large enterprises polluting natural water among many water users in an industrial region. This is made with the use of data on the concentrations of some priority water-polluting metals at the hydrochemical gages in the Iset river near Ekaterinburg City. The neural-network analysis is shown to detect relationships between individual water quality characteristics at nearby gages. This allowed the conclusion that there exist close logistic economic relationships between water users, which help revealing water pollutants by the water footprint produced by plants working in the same branch. It is also shown that the use of ANN opens new ways for determining the contribution of industrial waste discharges to the level of water pollution by substances of dual genesis (natural and technogenic). The reliability of the conclusions is confirmed by the possibility to use the data on a given hydrochemical gage to satisfactorily predict water quality at a gage further downstream. [ABSTRACT FROM AUTHOR]

It is well-known that the error of a measurement result can increase at each step of a laboratory procedure, as well as because of the sample character of partial measurements. To overcome these difficulties, close cooperation between hydrologists and analytical chemists is required in order to obtain reliable information about the composition and properties of natural waters, which are extremely unstable. The study focuses on details that are of importance for both the client-hydrologist and the performer—chemist-analyst. The article gives different variants of conclusions regarding the compliance or non-compliance with the established requirements. The cost of reliable measurements is calculated, and variants of optimization of enterprise's payments for discharges are proposed. Recommendations are given to customers regarding the choice of a competent analytical laboratory. [ABSTRACT FROM AUTHOR]

Averaged equations and 3D particle-in-cell modeling are used to examine the frequency multiplication regime in a high-current relativistic gyrotron operating in the 0.1 THz band of frequencies. It is shown that the ratio of the 3rd harmonic power output and the fundamental cyclotron resonance power can be as high as 0.4–0.8%, which allows 0.3 THz radiation with a sub-MW output power level to be obtained. [ABSTRACT FROM AUTHOR]

This article is devoted to the attempts of the administration of Joe Biden to normalize relations with radical leftist regimes (Cuba, Venezuela, and Nicaragua). At the same time, the negotiation process is complicated by bureaucratic and ideological difficulties. The purpose of this study is to identify key obstacles to improving interactions between Washington and the antagonist countries. The main trends in the foreign policy of the United States in the region, as well as the behavior of the governments of Latin American countries, will be analyzed. The results of this investigation will contribute to a better understanding of inter-American relations and will determine the trajectory of the transformation of the White House's course in the Western Hemisphere. [ABSTRACT FROM AUTHOR]

Modeling of gyrotrons by the particle-in-cell (PIC) method usually requires three-dimensional simulation. For large parameters of the oversized interaction space, this entails rather long calculation times. This work shows that one can reduce the dimension of the problem and employ 2.5-dimensional PIC simulation under certain conditions. Using a gyrotron with an operating frequency of 170 GHz and operating mode TE28, 12 as an example, the influence of an external signal on the output-radiation spectrum in the presence of accelerating-voltage fluctuations is studied [ABSTRACT FROM AUTHOR]

We present the main stages of developing a subgigawatt Ka-band gyrotron with the operating TM5, 1 mode. In order to discriminate the TE modes, we propose using a longitudinally slitted cavity, for which an analytical theory has been developed, calculations by the finite-element method have been made, and "cold" electrodynamic measurements (in the absence of an electron beam) have been performed. The first experimental studies of the gyrotron based on the classical scheme with separation of the beam formation space and the electron–wave interaction region have been carried out. The problem of the rise of parasitic oscillations at the TE mode, which are related to self-excitation of the beam formation region, has been revealed experimentally and within the framework of the three-dimensional simulation by the particle-in-cell method. A modification of the system, where the beam formation region shifts to the gyrotron cavity, is proposed as a way to solve this problem. Modeling has demonstrated the possibility to generate radiation with a power of about 150 MW in such a system. Preliminary calculations of a W-band gyrotron operated at the TM15, 1 mode with a similar output radiation power level have been made. [ABSTRACT FROM AUTHOR]

We study the dynamics of a W-band traveling-wave tube with delayed feedback on the basis of averaged equations and within the framework of three-dimensional simulation by the particle-in- cell method. The system parameters, which are optimal from the viewpoint of the width and uniformity of the chaotic-generation spectrum, are determined. It is shown that the chaotic noise-like radiation sources with the relative spectrum width exceeding 10% can be implemented using the experimentally realized traveling-wave tubes on the basis of a slow-wave system of the winding-waveguide type. [ABSTRACT FROM AUTHOR]

We present the results of studying experimentally gyroresonance K-band traveling-wave tubes having kilowatt power levels in the output radiation, in which the transition to multi-frequency generation regimes is implemented by the formation of relections of the output signal. It is shown that there exist regimes of significant interest for the problems of multi-frequency plasma heating, where the level of the second strongest spectral component is comparable with the level of the fundamental component. The problem of vacuum-window overheating during operation under the conditions of strong output-radiation reflections formed by a wideband Bragg reflector is discussed. [ABSTRACT FROM AUTHOR]

We propose a new type of a gyrotron cavity comprising the external and internal cylindrical resonators with azimuthally periodical axial slits. A theory of such a cavity is presented together with the eigenmode computation, which confirms its high mode selectivity. In 3D simulations using the particle-in-cells method, we compare the output characteristics of 0.5 THz gyrotrons with 0.1 to 1 kW output power. We demonstrate that as compared to a conventional solid wall cavity, the use of the novel-type cavity allows the smooth frequency tuning band to be increased by an order of magnitude and more. [ABSTRACT FROM AUTHOR]

Responsible gambling (RG) tools are globally widespread; they aim to prevent or decrease the harm caused by gambling. However, existing research suggests that several included features do not decrease gambling or significantly reduce the subsequent harm. Most of the previous studies have used gambling data to understand the changes in gambling behavior. However, the literature lacks research regarding gamblers' experience and perception of RG tools, which may provide insight into increasing the usage and effectiveness of RG tools. This mixed-methods study aimed to explore gamblers' perception of their risk assessment in the RG tool Playscan regarding developing harmful gambling problems. Overall, 757 participants rated the perceived accuracy of their risk assessment and their perception of the overall RG tool that conducted the assessment. Participants were also allowed to leave a comment providing feedback, which was analyzed using thematic analysis. Quantitative data was analyzed using logistic regression and structural equation modeling. Qualitative analyses revealed that most of the participants were pleased with the risk assessment and found it helpful. Moderated mediation analysis showed that participants' assessment agreement partially mediated the association between expressing a negative view and their general view of Playscan. These results highlight the need to decrease the level of disagreement for promoting a better general view of RG tools to potentially increase their usage and effectiveness. [ABSTRACT FROM AUTHOR]

Simulation of gyrotrons using the particle-in-cell method predominantly requires 3D calculations. At large oversize factors of the interaction space, it leads to lengthy calculation times. We show that under certain conditions, the dimensionality of the problem can be reduced and 2.5D PIC simulations can be applied. Using the example of a 170 GHz gyrotron with TE28,12 operating mode, we study the influence of the external signal on the noise level in the output radiation under conditions of fluctuations of the accelerating voltage. [ABSTRACT FROM AUTHOR]

Based on an analytical approach and numerical simulation, it is shown that, in an oversized cylindrical cavity with M longitudinal slits, the coupling of partial modes of a regular waveguide with M and 2M azimuthal indices can lead to the formation of high-Q modes with low radial losses at cut-off frequencies. This provides a possibility for selective excitation of such modes by helical electron beams in relativistic millimeter-wave gyrotrons. [ABSTRACT FROM AUTHOR]

The effect of pollutant in water on a population of aquatic organisms as a function of exposure time is studied. Natural assumptions are formulated regarding the character of this process, primarily, the linear relationship between the rate of decrease in the population, on the one hand, and the population size and the number of organisms killed by intoxication, on the other hand. The formulated assumptions are used to construct a model of population toxicodynamics, which describes the kinetics of suppression of the population by a logistic function. The results of model calculations are shown to agree with the available experimental data, thus justifying the formulated assumptions regarding the character of the intoxication process. An extension of the model is proposed through the incorporation of the dependence of the result of intoxication on pollutant concentration by the well-known Haber's formula. The developed model was used to propose an equation of regulated toxicodynamics for organization of water use without violation of the regime of natural functioning of ecosystems. The obtained specification of the notions of the mechanisms of intoxication process is necessary for the substantiation of hygienic standards on the concentration of chemicals in water, forecasts of biodiversity, and the choice of measures for supporting weak components of trophic chains in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

A new circuit of a dual-frequency radiation source based on an input signal-controlled self-excited gyroklystron amplifier is proposed. It is shown using the example of a high-power 3-mm-band gyroklystron that, varying the input signal frequency and power at the operation in the beat mode, i.e., beyond the synchronization band, one can implement a continuous independent tuning of the distance between spectral components in the range of 10‒150 MHz and of the ratio between their amplitudes from ‒10 to 0 dB. [ABSTRACT FROM AUTHOR]

Multifrequency oscillation regimes in a Ka-band pulsed gyro-backward wave oscillator based on a helically corrugated waveguide have been obtained. The pulsed radiation power is 30–35 kW at a pulse length of about 120 μs and a pulse repetition rate of up to 10 Hz. By changing the magnetostatic field in the interaction region and the pitch factor of particles, the oscillation center frequency has been tuned within 32‒35.5 GHz and the distance between the main spectral lines has been varied between 360‒550 MHz. [ABSTRACT FROM AUTHOR]

Oscillatory regimes with simultaneous excitation of several longitudinal modes of the overall electrodynamic system have been experimentally realized by introducing external reflections in a gyroresonance backward wave oscillator (gyro-BWO) based on a helical corrugated waveguide. Radiation in the 24-GHz band was obtained with an average power within 0.9–1.2 kW and a typical distance between spectral components 96- to 120-, 232- to 280-, and 464- to 640-MHz corresponding to the excitation of longitudinal modes with various indices. [ABSTRACT FROM AUTHOR]

The properties of natural waters are largely determined by the unique characteristics of this liquid; however, they are commonly not properly taken into account, and instead the concept of water as a continuous medium with foreign microcomponents is considered adequate. This approach is not appropriate for solving the problem of water resources management and the choice of innovation ways for the development of wet economic branches. A deeper study of the resource-economic properties of water should be based on molecular-dynamic models of this substance, the most important of which are described in this study. Many water-environmental processes are shown to be governed by the formation of ion-molecular associates and microstructural self-organization, determined by the specific properties of a grid of hydrogen bonds. This article is an analytical review (with some theoretical-experimental data of the authors), aimed to allow the reader to better understand the molecular-dynamic properties of water in the assessment of some water characteristics which are of importance for economic activity. [ABSTRACT FROM AUTHOR]

Summary: Abaloparatide increased ultradistal radius bone mineral density (BMD) in the Abaloparatide Comparator Trial in Vertebral Endpoints (ACTIVE) trial. Over the subsequent 24 months in ACTIVExtend, ultradistal radius BMD gains were maintained with alendronate. Conversely, 1/3 radius BMD remained stable during ALN treatment in ACTIVExtend after decreasing during ACTIVE. Introduction: Abaloparatide (ABL) increased femoral neck, total hip, and lumbar spine bone mineral density (BMD) in postmenopausal women with osteoporosis and decreased the risk of vertebral and nonvertebral fractures in ACTIVE. Effects on fracture risk and BMD were maintained subsequently with alendronate (ALN) in ACTIVExtend. In a prespecified subanalysis of ACTIVE, ABL also increased BMD at the ultradistal radius. Our objective was to determine the efficacy of ABL followed by ALN vs placebo (PBO) followed by ALN on forearm BMD and fracture risk over 43 months in ACTIVExtend. Methods: Ultradistal and 1/3 radius BMD (ACTIVE baseline to month 43) were measured (ABL/ALN, n = 213; PBO/ALN, n = 233). Wrist fracture rates were estimated for the ACTIVExtend intent-to-treat population (ABL/ALN, n = 558; PBO/ALN, n = 581) by Kaplan-Meier (KM) method. Results: At cumulative month 25, mean increase from ACTIVE baseline in ultradistal radius BMD was 1.1% (standard error, 0.49%) with ABL/ALN vs − 0.8% (0.43%) with PBO/ALN (P < 0.01). BMD increases with ABL were maintained with ALN through month 43 in ACTIVExtend. BMD decreases at the 1/3 radius in ACTIVE (similar with ABL and PBO) were maintained through 24 months of ALN treatment in ACTIVExtend. Wrist fractures over 43 months occurred in 15 women with ABL/ALN (KM estimate, 2.8%) and 20 with PBO/ALN (KM estimate, 3.6%) (HR = 0.77, 95% CI 0.39, 1.50; P = not significant). Conclusion: Ultradistal radius BMD gains following treatment with ABL in ACTIVE were maintained over 24 months of ALN treatment in ACTIVExtend. Conversely, 1/3 radius BMD remained stable during ALN treatment in ACTIVExtend after decreasing during ACTIVE. Trial registration: ClinicalTrials.gov: NCT01657162 submitted July 31, 2012 [ABSTRACT FROM AUTHOR]

A magnetron-injection gun able to provide very high ratio tj≈ 0.5 of the beam current to the Langmuir current has been designed, while maintaining good enough quality and stability of a formed helical electron beam. The specific feature of the gun is the shape of the cathode with two singular points of the electric field distribution which ensure close to uniform electric field profile within the emitter ring for wide range of operating currents. The gun provides the smoothed dependence of the beam parameters for currents up to 1.5–2 A and is suitable for wide (~ 10 GHz) frequency range gyrotron operation with the central frequency of 0.2 THz and output power ~ 1 kW within the whole tuning band. Such approach for the magnetron-injection gun design can be used for development of other promising high power sub-THz gyrotrons. [ABSTRACT FROM AUTHOR]

We study theoretically the possibility to widen the frequency tuning bandwidth of the generation of subterahertz gyrotrons by using strong signal reflections by periodic structures of the Bragg type installed in the output line. It was shown earlier that wideband tuning is possible in gyrotrons with short cavities, where the use of such cavities reduces the sensitivity of excitation of higher longitudinal modes to the spread of electron beam velocities. However, the issue of the formation of polyhelical electron beams with high currents arises in this case, and such beams are required to ensure the conditions of self-excitation in a short gyrotron cavity. The introduction of strong reflections allows one to significantly reduce the starting and operating currents, at which several higher longitudinal modes are excited. This ensures frequency tuning of about 8% at a power level of 0.5–1.0 kW with the use of electron beams which can be formed in magnetron-injection guns having the conventional geometry. [ABSTRACT FROM AUTHOR]

The effect of frequency multiplication was investigated for a fundamental-harmonic 0.263-THz kW-level gyrotron, in which a certain fraction of its radiation was observed experimentally at the doubled operating frequency. Accurate measurements of the power of such high-frequency generation were carried out based on cyclotron absorption of radiation in a HgTe/CdHgTe quantum-well heterostructure. The maximum power ratio of the second harmonic to the fundamental one is about 10−4 (an absolute power of 10–15 mW at a frequency of 0.526 THz), which agrees well with the results of simulations within the framework of the self-consistent averaged approach performed to describe the multimode generation in gyrotrons. [ABSTRACT FROM AUTHOR]

Intellectual disability is a neurodevelopmental disorder in which genetic, epigenetic and environmental factors are involved. In consequence, the determination of its etiology is usually complex. Though many countries have migrated from conventional cytogenetic analysis to chromosomal microarrays as the first-tier genetic test for patients with this condition, this last technique was implemented in our country a few years ago. We report on the results of the implementation of chromosomal microarrays in a cohort of 133 patients with intellectual disability and dysmorphic features, normal karyotype and normal subtelomeric MLPA results in an Argentinean public health institution. Clinically relevant copy number variants were found in 12% of the patients and one or more copy number variants classified as variants of uncertain significance were found in 5.3% of them. Although the diagnostic yield of chromosomal microarrays is greater than conventional cytogenetics for these patients, there are financial limitations to adopt this technique as a first-tier test in our country, especially in the public health system. [ABSTRACT FROM AUTHOR]

A cyclic wave nature of variations in the composition and properties of river water, indicating the long-term memory effect in the corresponding time series, has been discovered. This effect lies in the fact that the current values of the parameters under control to a great extent depend on their former values. The relation of long-term memory and persistence to the Hurst exponent and fractals of the investigated series has been specified. The possibility for quantitative estimation of the long-term memory effect has been established for controlled water use. [ABSTRACT FROM AUTHOR]

The optimum parameters for the generation of rogue waves (ultrashort pulses with peak powers several tens or hundreds of times higher than the average radiation power) in gyrotrons are determined. The possible generation of ultra-wideband chaotic millimeter radiation in gyrotrons with high-current relativistic beams is described. [ABSTRACT FROM AUTHOR]

A so-called shumotron (a chaotic oscillator with a continuous spectrum based on two coupled traveling wave tubes, one of which is an amplifier and the other acts as a nonlinear element) is modeled using a nonstationary distributed model of a traveling wave tube (TWT). The results can be used to develop a W-band noise generator based on experimentally realized pulsed TWTs with an output power level of tens of watts. [ABSTRACT FROM AUTHOR]

The possibility is considered of mastering higher injection currents and increasing the output power of high-current relativistic millimeter-wave gyrotrons using operating modes of the TM type. A longitudinally slotted cavity that ensures discrimination of parasitic TE-type modes is investigated via numerical modeling and experimental tests. The possibility of selectively exciting the TM51 mode with an output power of more than 200 MW and the TM71 mode with an output power of more than 300 MW is demonstrated. [ABSTRACT FROM AUTHOR]

World experience is analyzed to show that the role of standardization in water use management has increased considerably in the recent years. The state of the technical regulation of water use in the Russian Federation is considered, and the use of standardization in this sphere is shown to be not perfect. The main functions of standardization as an instrument of environmental management are determined. Examples are discussed to show that the lack of standards causes errors in the application of the Russian legislation now in force. An example shows how the described approach to standardization can be used to solve the problem of control of water advanced treatment by criterion of maximal benefit. [ABSTRACT FROM AUTHOR]

Observations show that the space and time heterogeneity of river water composition persists over indefinite time even when the effect of pollutant sources and sinks is minor. The driving forces of such heterogeneity have been supposed and shown to be, among other factors, the stratification of water matrix. Studying the structure of water flow and its effect on pollutant distribution in water was based on a system of fundamental equations of the mechanics of a liquid with a free surface. It has been shown that such effect is due to the fine structure of flows, vortices, waves and high-gradient interfaces (ligaments), which is formed and maintained by the motion of water masses. This conclusion extends our knowledge of the hydrological characteristics of water flow, enables one to better understand the nature of the heterogeneity of natural water composition, and it is of practical significance as such heterogeneity can be taken into account in making water management decisions. [ABSTRACT FROM AUTHOR]

The study focuses on the specific features of the justice dealing with the results of measuring the characteristics of safety and quality of production, works, or services. It is shown that the error (uncertainty) that appears in such situations is a measure of data scatter and a source of legal uncertainty, which causes a risk of judicial errors. The level of such risk increases with increasing demands of economy to the standardization of the ever-decreasing values of characteristics evaluated with higher uncertainty. The study shows that a necessary condition for the rule of law in such cases is the risk-oriented approach to resolving arbitration cases. [ABSTRACT FROM AUTHOR]

A complex chaotic dynamics in a gyrotron was experimentally observed under conditions of high supercriticality corresponding to 1000–1500-fold excess of the beam current parameter over the starting value. At electron beam currents typical of gyrotron test setups, this excess has been achieved by a transition to excitation of the lowest mode of a cylindrical waveguide. Chaotic generation regimes were observed in a 33 GHz frequency range with a spectral width of 500 MHz and record narrow relative width below 1.5% These results imply considerable progress in comparison to previous experiments with gyrotron type devices and are in good agreement with theoretical analysis based on a system of averaged evolution equations derived with allowance for finiteness of the transit time of electrons via the interaction space. [ABSTRACT FROM AUTHOR]

Purpose of Review: With the incidence of distal radius fractures increasing in the elderly population, we sought to summarize the current orthopedic and medical management of these fractures in the elderly osteoporotic population.Recent Findings: The number of osteoporotic patients undergoing surgical fixation for distal radius fractures has increased in recent years. This is likely due to the improved outcomes seen with volar locking plates, as well as an increase in the number of fellowship-trained hand surgeons. Despite this potential improvement in acute fracture management, a majority of these patients are underdiagnosed and undertreated for their underlying osteoporosis or endocrinopathies. The implementation of fracture liaison services and the ability of the treating orthopedist to recognize this gap in patient care result in a higher number of patients initiating appropriate treatment.Summary: It is vital that when discussing acute fracture management, a thorough discussion is had with patients regarding functional outcome and the benefits of both surgical and non-operative management. As these fractures become more prevalent and a greater percentage undergo surgical intervention, the economic burden of distal radius fractures will continue to rise. It is imperative that the treating surgeon view these fractures as sentinel events that are predictive of future hip and vertebral fractures. While relatively new, the use of fracture liaison services to help aide in proper screening and treatment of osteoporotic patients is of great value. Non-pharmacologic therapy such as physical therapy, smoking and alcohol cessation programs, and dietary modifications are crucial in treating patients with osteoporosis. While bisphosphonates remain the first-line treatment in patients with osteoporosis, novel therapies show promise for future use. [ABSTRACT FROM AUTHOR]

Rogue-waves in gyrotrons represent sporadically emitted ultrashort electromagnetic pulses with intensities significantly greater than the average radiation power and, in optimal conditions, higher than the power of the driving electron beams. In this paper within the framework of the average approach and direct 3D PIC (particle-in-cell) simulations, we study the possibility of rogue wave generation in submillimeter-band gyrotrons operating at high-order modes. It is demonstrated that in a 500 GHz fundamental cyclotron harmonic gyrotron excited by the 30 kV/50 A helical electron beam the peak power of generated picosecond electromagnetic spikes at TE61 mode can reach 5 MW that more than three times exceeds the power of the driving beam. [ABSTRACT FROM AUTHOR]

Anticoagulation is often used in superior vena cava syndrome (SVCS) associated with cancer (i.e malignant SVCS), even without thrombosis, but its effect on outcomes has not been reported. We aimed to determine factors and outcomes associated with thrombosis and anticoagulation in malignant SVCS. Patients with malignant SVCS diagnosed on computerized tomography (CT) were retrospectively included, indexed at diagnosis and followed for 6 months using medical records. The cohort included 183 patients with malignant SVCS of which 153 (84%) were symptomatic. Thirty of the 127 patients (24%) with a reviewable baseline CT had thrombosis of the SVC or tributaries at diagnosis. Patients with baseline thrombosis more often had symptomatic SVCS (p < 0.01). 70% (21/30) of patients with thrombosis and 52% (49/97) of those without thrombosis at baseline received anticoagulation, most often at therapeutic doses. Thrombosis occurred in 5/39 patients with anticoagulation (13%) compared to 2/18 (11%) of those without, during follow-up (p = 0.85). Anticoagulation was associated with a reduction in risk of SVC stent placement during follow-up that did not reach statistical significance (HR 0.47, 95% CI 0.2-1.13, p = 0.09). Major bleeding occurred in 7 (4%) patients, six of whom received anticoagulation (four therapeutic and two intermediate dose). Neither thrombosis nor anticoagulation affected survival. Anticoagulation is commonly used as primary prevention but its benefit remains to be proven. The role of reduced-dose anticoagulation in non-thrombotic malignant SVCS should be prospectively assessed. [ABSTRACT FROM AUTHOR]

A reliable quantitative assessment of the quality of river waters is difficult due to high variability of indexes being controlled and absence of information about the empirical function of the distribution of their probabilities. It is shown that in such a situation the expert-statistical method based on probabilistic interpretation of different variants of the Harrington desirability function may be useful. Such an approach makes is possible to solve the set problem using the Harrington scale for individual pollutants and for their combination with different hazard classes using a complex multiplicative criterion. The proposed approach of the expert-statistical assessment is illustrated by a practical example which may be recommended for general use. [ABSTRACT FROM AUTHOR]

Input signal connection circuits for a backward-wave tube with resonant reflector have been compared. It has been shown that the supply of radiation from an external source through an input cavity is more efficient than the supply from the collector side of the device. This advantage is reflected in higher linear gain of the input signal and lower power required for synchronization of the backward-wave tube self-oscillator by the external source. [ABSTRACT FROM AUTHOR]