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K. A. Fedin’s diaries related to the time of the intense activity of the literary community “Serapion brothers” (1921–1924) have not been preserved. Therefore, the material for the studies of the life of the group as well as of its separate members is obtained by the researchers in the epistolary legacy of the writer. The researchers hardly ever refer to the diaries of the later period, apparently believing that Serapion brothers entirely disappeared from the literary life after 1929. However, the Serapion theme still figures on the pages of Fedin’s diaries of the 1948–1968. It is of interest how the already renowned master contemplates the artistic problems which concerned all the “brothers” at the dawn of their writing youth, “general” mentions of the Serapion brothers in the context of the current dwellings on literature and art. Nevertheless, in the diaries of the period in question, certain writers connected by their general past of the “brothers” come to the foreground. Among them, first of all, are Vs. Ivanov, N. Tikhonov, M. Zoshchenko, V. Kaverin, M. Slonimsky, N. Nikitin. Each of them is an object of Fedin’s scrutiny, who responded to all the personal and creative events in the life of the “brothers”. The article presents, among other sources, previously unpublished materials, which provide a means of identifying the role of Serapion brothers on the pages of Fedin’s diaries of 1946–1968. They make it possible to include these references in the context of how the relationships of the writers – the former members of the group – developed, and to determine the degree to which this literary phenomenon influenced Fedin’s life.

The article analyzes the correspondence of E. G. Polonskaya and K. A. Fedin, members of the literary group Serapion Brothers, formed in Petrograd in 1921. The short but bright period of the existence of the association is still of interest to many researchers. Particularly relevant is the study of documentary sources, which make it possible to fi ll in the factual gaps in the history of both the Serapion fraternity itself and the relationships of its individual members. The author of the article draws on previously unpublished materials from the archive of K. A. Fedin and on their basis considers how the theme of Serapion is refl ected in the epistolary of Polonskaya and Fedin of 1925–1968. Of a particular interest is Polonskaya’s letter of 1925: written during the active work of Serapion Brothers, it refl ects the current view of the author on the events of the literary life of the 1920s. The bulk of the correspondence covers the period of the late 1950s – early 1960s. At this time, Polonskaya begins to work on her memoirs, some of which she dedicates to the Serapion Brothers: Konstantin Fedin and Mikhail Zoshchenko. She fi rst publishes them in 1963 in the Academic Proceedings of the Tartu State University. The manuscript sent to Fedin for review before publication becomes for the correspondents the starting point of a conversation about the uniqueness of the memoir genre, about the revival of interest in the Serapions, and about future research. The recurring theme of all letters is the feeling of belonging to the Serapion fraternity, friendly support over the years and the signifi cance of this for each of them.

This article examines what people conceal, who conceals from whom, and whether there are demographic differences in how much and what people conceal. We map concealment using a two-wave probability survey and behavioral experiment of U.S. adults (N = 1,281). Our survey measures self-reports of 37 different concealable attitudes, behaviors, and characteristics over a 12-month period, whereas the experiment provides a concrete behavioral measure of concealment. These data yield four principal findings. First, misinformation is commonplace in the United States, but it varies depending on what is being concealed. Second, certain demographic characteristics, such as age, predict rates of concealment, the proportion of things concealed, and lying in a behavioral experiment. Third, most demographic groups are similar in how much they conceal, but all demographic groups differ in what they conceal. Fourth, although some types of strong ties are more likely to be targets of concealment than weak ties, there is greater heterogeneity in concealment across different kinds of strong ties than between strong ties and weak ties, with spouses and partners being concealed from the least, on average. We conclude by discussing implications for theory and research on concealment. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is one of the most appealing radiotherapy modalities, whose localization can be further improved by the employment of boron-containing nanoformulations, but the fabrication of biologically friendly, water-dispersible nanoparticles (NPs) with high boron content and favorable physicochemical characteristics still presents a great challenge. Here, we explore the use of elemental boron (B) NPs (BNPs) fabricated using the methods of pulsed laser ablation in liquids as sensitizers of BNCT. Depending on the conditions of laser-ablative synthesis, the used NPs were amorphous (a-BNPs) or partially crystallized (pc-BNPs) with a mean size of 20 nm or 50 nm, respectively. Both types of BNPs were functionalized with polyethylene glycol polymer to improve colloidal stability and biocompatibility. The NPs did not initiate any toxicity effects up to concentrations of 500 µg/mL, based on the results of MTT and clonogenic assay tests. The cells with BNPs incubated at a 10B concentration of 40 µg/mL were then irradiated with a thermal neutron beam for 30 min. We found that the presence of BNPs led to a radical enhancement in cancer cell death, namely a drop in colony forming capacity of SW-620 cells down to 12.6% and 1.6% for a-BNPs and pc-BNPs, respectively, while the relevant colony-forming capacity for U87 cells dropped down to 17%. The effect of cell irradiation by neutron beam uniquely was negligible under these conditions. Finally, to estimate the dose and regimes of irradiation for future BNCT in vivo tests, we studied the biodistribution of boron under intratumoral administration of BNPs in immunodeficient SCID mice and recorded excellent retention of boron in tumors. The obtained data unambiguously evidenced the effect of a neutron therapy enhancement, which can be attributed to efficient BNP-mediated generation of α-particles. [ABSTRACT FROM AUTHOR]

The distributed computing infrastructure of the ATLAS Experiment includes over 170 sites and executes up to 3 million computing jobs daily. PanDA (Production and Distributed Analysis) is the Workload Management System responsible for task and job execution; its key components are the broker and job scheduler that define the mapping of computing jobs to the resources. The optimization of this mapping is crucial for handling the expected computational payloads during the HL-LHC era. Considering the heterogeneity and the distributed structure of the Worldwide LHC Computing Grid (WLCG) infrastructure that provides computing resources for analyzing the data, there is a need for specific approaches for evaluating computing resources according to their ability to process different types of workflows. This evaluation can potentially enhance the efficiency of the Grid by optimally distributing different types of payloads in heterogeneous computing environments. To tackle this challenge, this research proposes a method for evaluating WLCG resources regarding their ability to process user analysis payloads. This evaluation is based on leveraging available information about job execution on PanDA queues within the ATLAS computing environment. [ABSTRACT FROM AUTHOR]

The acquisition of reliable knowledge about the mechanism of short laser pulse interactions with semiconductor materials is an important step for high-tech technologies towards the development of new electronic devices, the functionalization of material surfaces with predesigned optical properties, and the manufacturing of nanorobots (such as nanoparticles) for bio-medical applications. The laser-induced nanostructuring of semiconductors, however, is a complex phenomenon with several interplaying processes occurring on a wide spatial and temporal scale. In this work, we apply the atomistic–continuum approach for modeling the interaction of an fs-laser pulse with a semiconductor target, using monolithic crystalline silicon (c-Si) and porous silicon (Si). This model addresses the kinetics of non-equilibrium laser-induced phase transitions with atomic resolution via molecular dynamics, whereas the effect of the laser-generated free carriers (electron–hole pairs) is accounted for via the dynamics of their density and temperature. The combined model was applied to study the microscopic mechanism of phase transitions during the laser-induced melting and ablation of monolithic crystalline (c-Si) and porous Si targets in a vacuum. The melting thresholds for the monolithic and porous targets were found to be 0.32 J/cm2 and 0.29 J/cm2, respectively. The limited heat conduction mechanism and the absence of internal stress accumulation were found to be involved in the processes responsible for the lowering of the melting threshold in the porous target. The results of this modeling were validated by comparing the melting thresholds obtained in the simulations to the experimental values. A difference in the mechanisms of ablation of the c-Si and porous Si targets was considered. Based on the simulation results, a prediction regarding the mechanism of the laser-assisted production of Si nanoparticles with the desired properties is drawn. [ABSTRACT FROM AUTHOR]

The production of non-toxic and homogeneous colloidal solutions of nanoparticles (NPs) for biomedical applications is of extreme importance nowadays. Among the various methods for generation of NPs, pulsed laser ablation in liquids (PLAL) has proven itself as a powerful and efficient tool in biomedical fields, allowing chemically pure silicon nanoparticles to be obtained. For example, laser-synthesized silicon nanoparticles (Si NPs) are widely used as contrast agents for bio visualization, as effective sensitizers of radiofrequency hyperthermia for cancer theranostics, in photodynamic therapy, as carriers of therapeutic radionuclides in nuclear nanomedicine, etc. Due to a number of complex and interrelated processes involved in the laser ablation phenomenon, however, the final characteristics of the resulting particles are difficult to control, and the obtained colloidal solutions frequently have broad and multimodal size distribution. Therefore, the subsequent fragmentation of the obtained NPs in the colloidal solutions due to pulsed laser irradiation can be utilized. The resulting NPs' characteristics, however, depend on the parameters of laser irradiation as well as on the irradiated material and surrounding media properties. Thus, reliable knowledge of the mechanism of NP fragmentation is necessary for generation of a colloidal solution with NPs of predesigned properties. To investigate the mechanism of a laser-assisted NP fragmentation process, in this work, we perform a large-scale molecular dynamics (MD) modeling of FS laser interaction with colloidal solution of Si NPs. The obtained NPs are then characterized by their shape and morphological properties. The corresponding conclusion about the relative input of the properties of different laser-induced processes and materials to the mechanism of NP generation is drawn. [ABSTRACT FROM AUTHOR]

Featured Application: Electrochromic devices, such as smart windows. The goal of this work was the synthesis study of the [WO2(C5H7O2)2] complex and its application as a precursor for the growth of WO3 films in hydrothermal conditions, as well as evaluating the microstructural features and electrochromic properties of the formed materials. Dioxotungsten acetylacetonate was synthesized in an aqueous medium and purified. It was found that during hydrothermal treatment of the alcohol solution of the complex, acetylacetonate ligands undergo partial destructive substitution by alkoxyl groups, intensifying at temperatures above 140 °C. Considering these data and using a [WO2(C5H7O2)2] solution, WO3 films were grown on glass and glass/ITO substrates. The resulting films had different microstructures according to scanning electron microscopy (SEM) and atomic force microscopy (AFM): the former consisted of submicron spheres (~500 nm), distinct nanoparticles (60–160 nm), and submicron- and micron-sized ridges, while the latter consisted of 1D structures (length 350 ± 25 nm, width 110 ± 25 nm). Using Kelvin probe force microscopy (KPFM), the electron work function was determined for the film on glass/ITO substrate (4.77 eV). It was found that the electrochemical coloration process of the obtained WO3 film can proceed in two stages, and the optical contrast is about 17.5% (at the wavelengths of 600–1100 nm). The results obtained show the prospects of applying the proposed approach to obtaining WO3 electrochromic films with a hierarchical microstructure with the hydrothermal method using the [WO2(C5H7O2)2] complex as a precursor. [ABSTRACT FROM AUTHOR]

Proton therapy is one of the promising radiotherapy modalities for the treatment of deep-seated and unresectable tumors, and its efficiency can further be enhanced by using boron-containing substances. Here, we explore the use of elemental boron (B) nanoparticles (NPs) as sensitizers for proton therapy enhancement. Prepared by methods of pulsed laser ablation in water, the used B NPs had a mean size of 50 nm, while a subsequent functionalization of the NPs by polyethylene glycol improved their colloidal stability in buffers. Laser-synthesized B NPs were efficiently absorbed by MNNG/Hos human osteosarcoma cells and did not demonstrate any remarkable toxicity effects up to concentrations of 100 ppm, as followed from the results of the MTT and clonogenic assay tests. Then, we assessed the efficiency of B NPs as sensitizers of cancer cell death under irradiation by a 160.5 MeV proton beam. The irradiation of MNNG/Hos cells at a dose of 3 Gy in the presence of 80 and 100 ppm of B NPs led to a 2- and 2.7-fold decrease in the number of formed cell colonies compared to control samples irradiated in the absence of NPs. The obtained data unambiguously evidenced the effect of a strong proton therapy enhancement mediated by B NPs. We also found that the proton beam irradiation of B NPs leads to the generation of reactive oxygen species (ROS), which evidences a possible involvement of the non-nuclear mechanism of cancer cell death related to oxidative stress. Offering a series of advantages, including a passive targeting option and the possibility of additional theranostic functionalities based on the intrinsic properties of B NPs (e.g., photothermal therapy or neutron boron capture therapy), the proposed concept promises a major advancement in proton beam-based cancer treatment. [ABSTRACT FROM AUTHOR]

Operational analytics is the direction of research related to the analysis of the current state of computing processes and the prediction of future states in order to anticipate imbalances and take timely measures to stabilize a complex system. There are two relevant areas in ATLAS Distributed Computing that are currently the focus of studies: user physics analysis including the forecast of popularity of data samples among users, and evaluating WLCG centers for their readiness to process user analysis payloads. Studying these areas is challenging due to the complexity involved, as it requires a comprehensive understanding of numerous boundary conditions typically found in large-scale distributed computing infrastructures. Forecasts of data popularity are problematic without the categorization of user tasks by their types (data transformation or physics analysis), which do not always appear on the surface but may induce noise, which introduces significant distortions for predictive analysis. Evaluating the WLCG resources by their analysis workloads is also a challenging task as it is necessary to find a balance between the workload of the resource, its performance, the waiting time for jobs on it, as well as the volume of jobs that it processes. This is especially difficult in a heterogeneous computing environment, where legacy resources are used along with modern high-performance machines. We will look at these areas of research in detail and discuss what tools and methods are used in our work, demonstrating results already obtained.