Dynamics of Metastable Vacua in the Early Universe

We study the question whether a possible metastable vacuum state is actually populated in a phase transition in the early universe, as is usually assumed in the discussion of vacuum stability bounds e.g. for Standard Model parameters. A phenomenological (3+1)-dimensional Langevin equation is solved numerically for a toy model with a potential motivated by the finite temperature 1-loop effective potential of the Standard Model including additional non-renormalizable operators from an effective theory for physics beyond the Standard Model and a time dependent temperature. It turns out that whether the metastable vacuum is populated depends critically on the value of the phenomenological parameter eta for small scalar couplings. For large enough scalar couplings and with our specific form of the non-renormalizable operators the system (governed by the Langevin equation) always ends up in the metastable minimum.Comment: Some additional discussion, references added, final version to appear in Phys.Lett.

Efficient technology of human resources management in the field of transport

The authors of the article strive to give an analysis of the main aspects of human resource management technology in the practice of transport companies, to identify the problematic issues of their development and to find solutions. The article discusses the criteria for effective human resource management, analyzes the conditions for monitoring the quality of human resource use in a transport company, describes the characteristics of grading as an effective management technology for the motivational component of the personnel in the transport sector. As an experimental base of research, the authors used monitoring the quality of human resources in transport companies of the city of Tyumen - Evrobus 72, IntelInvest, ComfortAuto Tyumen, as well as textual and graphical materials of reports

Topic model visualization with IPython

The paper introduces an approach to topic model visualization that is characterized by wide possibilities of choosing a method of visualization, user-friendly model representation, and simplicity of implementation for applications. The existing approaches to topic models visualization have been analyzed, and a system, which allows choosing data source for topic models, changing modeling parameters and visualizing the result of topic modeling with IPython has been developed. The example of topic model visualization has been built using the SCTM-en corpus of original news text

Studying perceptual bias in favor of the from-above Necker cube perspective in a goal-directed behavior

When viewing a completely ambiguous image, different interpretations can switch involuntarily due to internal top-down processing. In the case of the Necker cube, an entirely ambiguous stimulus, observers often display a bias in perceptual switching between two interpretations based on their perspectives: one with a from-above perspective (FA) and the other with a from-below perspective (FB). Typically, observers exhibit a priori top-down bias in favor of the FA interpretation, which may stem from a statistical tendency in everyday life where we more frequently observe objects from above. However, it remains unclear whether this perceptual bias persists when individuals voluntarily decide on the Necker cube's interpretation in goal-directed behavior, and the impact of ambiguity in this context is not well-understood. In our study, we instructed observers to voluntarily identify the orientation of a Necker cube while manipulating its ambiguity from low (LA) to high (HA). Our investigation aimed to test two hypotheses: (i) whether the perspective (FA or FB) would result in a bias in response time, and (ii) whether this bias would depend on the level of stimulus ambiguity. Additionally, we analyzed electroencephalogram (EEG) signals to identify potential biomarkers that could explain the observed perceptual bias. The behavioral results confirmed a perceptual bias in favor of the from-above perspective, as indicated by shorter response times. However, this bias diminished for stimuli with high ambiguity. For the LA stimuli, the occipital theta-band power consistently exceeded the frontal theta-band power throughout most of the decision-making time. In contrast, for the HA stimuli, the frontal theta-band power started to exceed the occipital theta-band power during the 0.3-s period preceding the decision. We propose that occipital theta-band power reflects evidence accumulation, while frontal theta-band power reflects its evaluation and decision-making processes. For the FB perspective, occipital theta-band power exhibited higher values and dominated over a longer duration, leading to an overall increase in response time. These results suggest that more information and more time are needed to encode stimuli with a FB perspective, as this template is less common for the observers compared to the template for a cube with a FA perspective

Multi-spectroscopic study of electrochemically-formed oxide-derived gold electrodes

Oxide-derived metals are produced by reducing an oxide precursor. These materials, including gold, have shown improved catalytic performance over many native metals. The origin of this improvement for gold is not yet understood. In this study, operando non-resonant sum frequency generation (SFG) and ex situ high-pressure X-ray photoelectron spectroscopy (HP-XPS) have been employed to investigate electrochemically-formed oxide-derived gold (OD-Au) from polycrystalline gold surfaces. A range of different oxidizing conditions were used to form OD-Au in acidic aqueous medium (H3PO4, pH = 1). Our electrochemical data after OD-Au is generated suggest that the surface is metallic gold, however SFG signal variations indicate the presence of subsurface gold oxide remnants between the metallic gold surface layer and bulk gold. The HP-XPS results suggest that this subsurface gold oxide could be in the form of Au2O3 or Au(OH)3. Furthermore, the SFG measurements show that with reducing electrochemical treatments the original gold metallic state can be restored, meaning the subsurface gold oxide is released. This work demonstrates that remnants of gold oxide persist beneath the topmost gold layer when the OD-Au is created, potentially facilitating the understanding of the improved catalytic properties of OD-Au.Peer reviewe

Observational study of pimecrolimus 1% cream for prevention of transcutaneous sensitization in children with atopic dermatitis during their first year of life

IntroductionEpidermal barrier dysfunction in children with atopic dermatitis can cause transcutaneous sensitization to allergens and allergic diseases. We evaluated the effectiveness of an early-intervention algorithm for atopic dermatitis treatment, utilizing pimecrolimus for long-term maintenance therapy, in reducing transcutaneous sensitization in infants.MethodThis was a single-center cohort observational study that enrolled children aged 1-4 months with family history of allergic diseases, moderate-to-severe atopic dermatitis, and sensitization to ≥ 1 of the investigated allergens. Patients who sought medical attention at atopic dermatitis onset (within 10 days) were group 1 “baseline therapy with topical glucocorticoids with subsequent transition to pimecrolimus as maintenance therapy”; patients who sought medical attention later were group 2 “baseline and maintenance therapy with topical glucocorticoids, without subsequent use of pimecrolimus”. Sensitization class and level of allergen-specific immunoglobulin E were determined at baseline, and 6 and 12 months of age. Atopic dermatitis severity was evaluated using the Eczema Area and Severity Index score at baseline and 6, 9 and 12 months of age.ResultsFifty-six and 52 patients were enrolled in groups 1 and 2, respectively. Compared with group 2, group 1 demonstrated a lower level of sensitization to cow's milk protein, egg white and house dust mite allergen at 6 and 12 months of age, and a more pronounced decrease in atopic dermatitis severity at 6, 9 and 12 months of age. No adverse events occurred.DiscussionThe pimecrolimus-containing algorithm was effective in treating atopic dermatitis and prophylaxis of early forms of allergic diseases in infants.Trial registrationhttps://clinicaltrials.gov/NCT04900948, retrospectively registered, 25 May 2021

Efficient technology of human resources management in the field of transport

The authors of the article strive to give an analysis of the main aspects of human resource management technology in the practice of transport companies, to identify the problematic issues of their development and to find solutions. The article discusses the criteria for effective human resource management, analyzes the conditions for monitoring the quality of human resource use in a transport company, describes the characteristics of grading as an effective management technology for the motivational component of the personnel in the transport sector. As an experimental base of research, the authors used monitoring the quality of human resources in transport companies of the city of Tyumen - Evrobus 72, IntelInvest, ComfortAuto Tyumen, as well as textual and graphical materials of reports