Big Drop Research Articles

Influence of the number of holes and two types of PCM in brick on the heat flux passing through the wall of a building on a sunny day in Medina, Saudi Arabia

In this article, the impact of using two types of phase change material (PCM) in brick on a summer day according to the climate of Medina, Saudi Arabia is studied numerically. Bricks with square holes filled with PCM are used for the inner sidewall. For this purpose, PCMs P116 and n-Eicosane are used to fill the bricks and are compared with the case without PCM to determine its effect on the amount of heat flux passing (HEFP) through the wall. The effect of the different number of holes (1–4) is also studied. Two-dimensional numerical simulations are performed using the control volume method. The results show that the maximum HEFP through the wall occurs in the afternoon. Examination of the melting front of PCMs indicates that the melting front moves from the hot wall toward the cold wall and the type of PCM are important during the completion of the melting process. In general, the usage of PCM minimizes the amount of HEFP through the wall. The usage of PCM n-Eicosane results in a greater decrease in the quantity of heat flux going through the wall. At midday, the biggest drop in heat flow occurs. Using additional holes, particularly when the bricks are filled with PCM n-Eicosane, dramatically lowers the HEFP through the wall. The kind of PCM used to decrease flux going through the wall is determined by the temperature of the building.

Optimizing the Distribution Transformer Placement Based on the Maximum Loading and Drop Voltage at PLN Tegalsari Rayon

One of Problems in Indonesia regarding electricity distribution is far power station from the load (consumer). As a result, the electric energy distribution often becomes ineffective due to big enough voltage drop along the transmission and distribution channels. To overcome this problem, voltage drop must be reduced by placing the distribution transformer optimally. Therefore, this research aimed at determining the new distance from the transformer obtaining voltage drop above 10% along the channel of PLN Ltd in Tegalsari Rayon. For this reason, the researcher employed maximum loading on a certain bus or Continous Power Flow (CPF) and calculated the voltage drop in each channel simulated by Matlab. The simulation results demonstrated that bus 2 gained the maximum load 7.8 times, consequently, there were 15 buses getting voltage drop more than10%. Those buses comprised: bus 6 0.9%, bus 7 11.6%, bus 8 14.3%, bus 9 14.3%, bus 10 16.1%, bus 11 16.2%, bus 12 17.9%, bus 13 17.6%, bus 14 17.5%, bus 15 17%, bus 16 17%, bus 17 16.9%, bus 18 16.8%, bus 19 16.8%, and 20 16.8%. Meanwhile, the alteration of new distances occurring in several buses included: bus 6 from 151.9 m to 138.784 m, bus 7 from 48 m to 41.184 m, bus 8 from 211 m to 146.884 m, bus 9 from 50 m to 34.734 m, bus 10 from 205.89 m to 127.842 m, bus 11 to 167.01 m, bus 12 to 316.23 m, bus 13 to 141.44 m, bus 14 to 17.9 m, bus 15 to 1141.85 m, bus 16 to 19.61 m, bus 17 to 38.13 m, bus 18 to 59.31 m, bus 19 to 13.33 m, and 20 to 19.99 m.

Achieving Multisite Generalization for CNN-Based Disease Diagnosis Models by Mitigating Shortcut Learning

When a learned model has high accuracy under familiar settings (internal testing) and a big drop in accuracy under slightly different circumstances (external testing) we suspect it is using shortcuts to make decisions. This problem is known as shortcut learning. In medical imaging, shortcuts are undesired and unintended features that the model relies on to perform diagnosis. Shortcut-based solutions using medical images could lead to false diagnoses and have dangerous implications for patients. In the current COVID-19 era, a large set of papers have been published proposing the use of deep convolutional neural networks to perform diagnosis or triage of COVID-19 from chest X-rays (CXRs). These studies are reporting high accuracies which could be misleading and overestimated. To our knowledge, none of the currently published papers with high performance reported testing on samples from truly unseen data sources. Studies which did, have noticed a significant performance drop when testing on unseen sources indicating a failure to generalize. In this paper, we elucidate the generalization challenge of deep learning based models trained for disease diagnosis. We use the example of COVID-19 diagnosis from CXRs. Solutions that mitigate shortcut learning are introduced and experimentally shown to be effective. Our proposed methods enable the models to have a statistically significantly reduced performance drop-off on unseen data sources. Thus, lowering the performance drop to only 9% instead of 20%. The issues with convolutional neural networks addressed here generally apply to other imaging modalities and recognition problems, as shown.

Наслідки війни в Україні для національного ринку праці та напрями підтримки зайнятості

Nowadays Ukrainian society is faced with a new problem of preserving social and economic capital, maintaining socioeconomic balance and forming strategies for the further postwar recovery of the country, which requires an assessment of the state of the national labor market with the development of proposals for supporting the employment of the population. Therefore, the article is aimed at evaluating the consequences of the war in Ukraine in terms of a decrease in the level of employment, determining the directions for preserving / creating jobs, taking into account the present conditions where Ukraine has to deal with military hostilities, taking into account the principles of forming a competitive economy. The article is concerned with outlining the main threats of war for the national labor market with the definition of the main directions of the employment support. The loss of labor potential is analyzed, which is one of the acute humanitarian problems. Based on the calculation of the coefficient of elasticity of employment, a forecast of a decrease in the level of employment in 2022 appears as a result of a decline in the economy because of military actions on the territory of Ukraine. The biggest drops in employment are possible with a 50% drop in GDP and an increased sensitivity between falling GDP and employment. Therefore, the State regulation of the labor market should take place taking into account the fact that during the recession it is necessary to reduce such sensitivity, and with the subsequent postwar recovery of the economy is important, on the contrary, to increase the sensitivity between GDP growth and employment to ensure maximum social and labor involvement of the population of Ukraine, which is quite possible with a large-scale reconstruction of the country and the development of the economy, which will be accompanied by an increase in demand for labor. Measures are proposed to support employment in accordance with the conditions of the national economy of wartime, which will contribute to an increase in the level of GDP and the level of income of the population. The role of non-standard forms of employment in coordinating the negative consequences of the economic crisis in Ukraine is determined. It is proposed to use such programs to protect wage recipients as «work-sharing», subsidization of wages, etc.

Diagnostic and Therapeutic Potential of Exosomes in Neurodegenerative Diseases.

Neurodegenerative diseases are closely related to brain function and the progression of the diseases are irreversible. Due to brain tissue being not easy to acquire, the study of the pathophysiology of neurodegenerative disorders has many limitations—lack of reliable early biomarkers and personalized treatment. At the same time, the blood-brain barrier (BBB) limits most of the drug molecules into the damaged areas of the brain, which makes a big drop in the effect of drug treatment. Exosomes, a kind of endogenous nanoscale vesicles, play a key role in cell signaling through the transmission of genetic information and proteins between cells. Because of the ability to cross the BBB, exosomes are expected to link peripheral changes to central nervous system (CNS) events as potential biomarkers, and can even be used as a therapeutic carrier to deliver molecules specifically to CNS. Here we summarize the role of exosomes in pathophysiology, diagnosis, prognosis, and treatment of some neurodegenerative diseases (Alzheimer’s Disease, Parkinson’s Disease, Huntington’s Disease, Amyotrophic Lateral Sclerosis).

Combustion and Emission Characteristics of Dual Fuel Engine for Different Parameters

The effects of compression ratio and fuel delivery advance angle on the combustion and emission characteristics of premixed methanol charge induced ignition by Fischer Tropsch diesel engine were investigated using a CY25TQ diesel engine. In the process of reducing the compression ratio from 16.9 to 15.4, the starting point of combustion is fluctuating, the peak of in-cylinder pressure and the maximum pressure increase rate decrease by 44.5% and 37.7% respectively. The peak instantaneous heat release rate increases by 54.4%. HC and CO emissions are on a rising trend. NOx and soot emissions were greatly decreased. The soot emission has the biggest drop of 50%. Reducing the fuel delivery advance angle will make the peak of in-cylinder pressure and the peak of pressure rise rate increase while the peak of heat release rate decreases. The soot emission is negatively correlated with the fuel delivery advance angle. When the fuel delivery advance angle is 16° CA, the soot emissions increased the most by 130%.

Echocardiographic assessment of left ventricular function in ex situ heart perfusion using pump-supported and passive afterload working mode: a pilot study

Ex situ heart perfusion (ESHP) has been developed to decrease cold ischemia time and allow metabolic assessment of donor hearts prior to transplantation. Current clinical ESHP systems preserve the heart in an unloaded condition and only evaluate the cardiac metabolic profile. In this pilot study we performed echocardiographic functional assessment using two alternative systems for left ventricular (LV) loading: pump supported afterload working mode (SAM) and passive afterload working modes (PAM). Six hearts were procured from male Yorkshire pigs. During cold ischemia, hearts were mounted on our custom made ESHP circuit and a 3D-printed enclosure for the performance of echocardiography with a standard TEE probe. Following perfusion with Langherdorf mode of the unloaded heart, the system was switched into different working modes to allow LV loading and functional assessment: pump supported (SAM) and passive (PAM). Echocardiographic assessment of left ventricular function in the donor hearts was performed in vivo and at 1 h of ESHP with SAM, after 4.5 h with PAM and after 5.5 h with SAM. We obtained good quality epicardial echocardiographic images at all time points allowing a comprehensive LV systolic assessment. All indices showed a decrease in LV systolic function throughout the trial with the biggest drop after heart harvesting. We demonstrated the feasibility of echocardiographic functional assessment during ESHP and two different working modes. The expected LV systolic dysfunction consisted of a reduction in EF, FAC, FS, and strain throughout the experiment with the most significant decrease after harvesting.

ОСОБЛИВОСТІ МЕДІАСПОЖИВАННЯ УКРАЇНЦІВ ПІД ЧАС ПАНДЕМІЇ

<p><strong><em>The purpose </em></strong><em>of the study is to conduct a detailed scientific and practical substantiation of the peculiarities of media consumption of Ukrainians during the pandemic, and to conduct a survey to establish which media Ukrainians use before and during the COVID-19 pandemic.</em></p><p><strong><em>Research methodology.</em></strong><em> The study provides a comprehensive analysis of the characteristics of media consumption of Ukrainians during the COVID-19 pandemic. For this purpose the theoretical methodological case including the description, the analysis and synthesis is used; analytical modeling; comparative analysis; systematization, generalization and survey.</em></p><p><strong><em>Results.</em></strong><em> The results of the study showed that, among social networks as news sources, Facebook tops the list for several years in a row, YouTube has become as an alternative to television, and Telegram is most often used to receive short news. Respondents said that they mostly watched the news using the following devices: mobile phone, computer and TV. The biggest drop in 2020 was in the level of trust in television – the main reasons for the lack of trust are inaccurate information and political bias in the news. The share of Ukrainian Internet users increased from 71% in 2015 to 90% of Ukrainians in 2020. For the younger demographic group aged 18-35, this figure rises to 100%. Accordingly, online media and social networks are more popular among Ukrainians aged 18-35, while Ukrainians over the age of 46 prefer television.</em></p><p><strong><em>Novelty.</em></strong><em> The scientific novelty is due to the solution of an important scientific task, which is to develop practical recommendations on the peculiarities of media consumption of Ukrainians during the COVID-19 pandemic. It was established which social networks and mass media Ukrainians use most often, and whether Ukrainians trust the news and which news topics they prefer.</em></p><p><strong><em>Practical significance.</em></strong><em> The results of the study are intended to serve for further research to explore new features of media consumption of Ukrainians during the COVID-19 pandemic and to inform about the current course of COVID-19, which will help to better understand the role of specialized media content.</em></p><p><strong><em>Key words:</em></strong><em> media, media consumption, mass media, pandemic, COVID-19.</em></p>

Effect of the oxygen concentration on the combustion of asphalt binder

The combustion mechanism and gaseous products of asphalt binder at five different oxygen concentrations (21%, 18%, 15%, 12%, and 10%) were studied by thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR). The evolution of the functional groups and microscopic morphology of condensed phase were also analyzed by infrared spectroscopy (IR) and scanning electron microscopy (SEM). The semi quantitative research was realized by calculating the absorption peak area of IR, proximate and ultimate analyses. Results show that the oxygen concentration influences both the pyrolysis and combustion stages of asphalt, and the influence on the combustion of heavy components is more significant. With the decrease of oxygen concentration, the residual mass after the combustion of asphalt binder increases. Additionally, the temperature zone of combustion shifts higher, and a thermal reaction lag effect becomes more obvious. The concentration of oxygen only changes the concentration of gaseous products, instead of the types. Moreover, the concentrations of CO2, CO, H2O, SO2, etc. all decrease, and there is the biggest drop in CO2. The low oxygen concentration inhibits the dehydrogenation reaction of asphalt in the aerobic pyrolysis stage, while the complete combustion of asphalt residues is inhibited in the combustion of heavy components stage. These will all provide more scientific basis for the analysis of asphalt combustion under low oxygen conditions in tunnel fires.

An efficient phase-field method for turbulent multiphase flows

With the aim of efficiently simulating three-dimensional multiphase turbulent flows with a phase-field method, we propose a new discretization scheme for the biharmonic term (the 4th-order derivative term) of the Cahn-Hilliard equation. This novel scheme can significantly reduce the computational cost while retaining the same accuracy as the original procedure. Our phase-field method is built on top of a direct numerical simulation solver, named AFiD (www.afid.eu) and open-sourced by our research group. It relies on a pencil distributed parallel strategy and a FFT-based Poisson solver. To deal with large density ratios between the two phases, a pressure split method [1] has been applied to the Poisson solver. To further reduce computational costs, we implement a multiple-resolution algorithm which decouples the discretizations for the Navier-Stokes equations and the scalar equation: while a stretched wall-resolving grid is used for the Navier-Stokes equations, for the Cahn-Hilliard equation we use a fine uniform mesh. The present method shows excellent computational performance for large-scale computation: on meshes up to 8 billion nodes and 3072 CPU cores, a multiphase flow needs only slightly less than 1.5 times the CPU time of the single-phase flow solver on the same grid. The present method is validated by comparing the results to previous studies for the cases of drop deformation in shear flow, including the convergence test with mesh refinement, and breakup of a rising buoyant bubble with density ratio up to 1000. Finally, we simulate the breakup of a big drop and the coalescence of O(103) drops in turbulent Rayleigh-Bénard convection at a Rayleigh number of 108, observing good agreement with theoretical results.

Montevideo, walkable city: pedestrianization of a large avenue during 2020 pandemic

On March 13, 2020, the first cases of SARS-COVID19 were detected in Uruguay. During the first weeks of the pandemic, mobility was significantly reduced with the slogan "If you can, stay home"; it was not a mandatory but voluntary confinement. After a couple of months, there was a big drop in the number of people affected by the disease. Thus, the Municipality of Montevideo, betting on a more human and walkable city, defined that the main avenue of the city had a pedestrian section on Saturday afternoons. This resulted in a greater enjoyment of the city by its inhabitants, as they had more space to walk while maintaining safe distances between people. It was also possible to promote trading, since classically Ave. 18 de Julio is also a commercial stroll. Additionally, the sound pressure levels recorded by the Municipality's stationary sound level meters located at three points along the avenue, showed the reduction of environmental sound levels in pedestrian areas, improving the acoustic quality of the walk. In this paper, sound pressure levels on Saturday afternoons at different times of the year before, during and after the initial lockdown due to the COVID-19 pandemic, are compared and discussed.

Early years providers

The pandemic has seen a big drop in childcare provision with thousands of providers leaving the Ofsted register. Jo Stephenson speaks to early years groups about what must change to stem the decline

Dynamic high pressure microfluidization (DHPM): Physicochemical properties, nutritional constituents and microorganisms of yam juice

Dynamic high pressure microfluidization (DHPM) is considered an emerging and promising technique for the continuous production of fluid foods. This study measured the effect of DHPM on yam juice. After DHPM processing, the content of total soluble solids (TSS), turbidity, flavonoid and non-enzymatic browning was significantly decreased, with the biggest drops being 35.5, 86.2, 20.7, and 66.7%, respectively. Moreover, the average particle size was decreased from 1 944 nm to 358 nm, which showed a strong positive correlation with turbidity. The reduction coefficients and electric conductivity of Escherichia coli, Saccharomyces cerevisiae and Lactobacillus plantarum were increased significantly after DHPM processing. Combined with morphological analysis, DHPM processing had good bactericidal effects on E. coli and S. cerevisiae. These results provided reference values for the application of DHPM technology in the development of yam juice.

The potential impact of biochar: Soil hydraulics and responses of maize under soil drying cycles

Biochar (BC) has been shown to positively impact soil hydraulic properties. However, its effect on water flow in unsaturated soil and root access to water have been poorly understood. This study was conducted to investigate the potential impact of BC application on soil water accessibility and plant responses under soil drying cycles.A grapevine wood-based BC was mixed with a sandy loam soil at the rates of 0, 20, and 40 g kg−1 and preincubated in the PVC pots for two months. Then, maize plants were grown in preincubated pots and regularly irrigated during their vegetative phase (64 days) to maintain soil moisture at optimum condition (0.30 cm3 cm−3). Thereafter, plants were subjected to repeated soil drying (via plant transpiration) and wetting cycles (via irrigation from the top) with soil water content varying between 0.18 and 0.30 cm3 cm−3, respectively. Some selected plant growth parameters and plant physiological responses to soil drying cycles were determined. In parallel, soil water retention and hydraulic conductivity curves of different treatments were measured by a combination of the sandbox, pressure plate apparatus, and Hyprop.The results showed that plant dry shoot biomass was slightly increased by the BC application (9% on average). In contrast, the leaf area and root volume did not show any significant difference. As soil dried during a soil drying cycle, the transpiration rate decreased among all treatments. However, the drop in transpiration rate was smaller in the BC-amended soils than in the control. At soil water content of 018 cm3 cm−3, plants grown in BC-amended soils had on average 83% and 164% higher transpiration and photosynthesis rate than plants grown in control soil, respectively. These comparisons suggest that BC improved water accessibility to plants during soil drying, resulting in 76 and 58% increase in grain yield and grain water productivity. The application of BC had little effect on soil water retention in the wet range and had no impacts in the drier range, while the unsaturated hydraulic conductivity (Kh) and calculated matric flux potential (φ) were positively impacted in a wide range of soil water content.The findings of this study revealed that BC mixed with sandy loam soil could prevent a big drop in Kh as soil dries, thereby improving root access to water and transpiration rate under drought stress.

Q&A: Ned Sharpless on COVID-19 and Cancer Prevention.

Q&A: Ned Sharpless on COVID-19 and Cancer Prevention.

Single and Double Drop Impingement on a Heated Plate CFD and Experimental Investigation

A drop impingement on a hot surface is known as an effective way for heat removal. The present work uses a VOF (volume of fluid) model to simulate the flow behavior and temperature distribution on a 50 °C heated plate while relatively cold water drop is impinging. The temperature distribution at the impingement zone is used to examine the transient heat transfer coefficients using a single drop and double drops conditions. The spreading factor is tested in both cases. A test rig is built to verify the temperature distribution and a heat balance method is introduced to find the experimental heat coefficients on the heated. The CFD solution and its flow results gives a good agreement for single drop previous results. The results for the double drop condition show a high tendency for rebound and splash of the drop leaving the central zone without water drop coverage which way causes a burn out in case of high heat fluxes. The single drop condition show a symmetrical temperature and heat transfer coefficients distribution while the double drop impingement gives lower value of coefficients with non-uniform and unsymmetrical distribution specially at the bigger drop to plate distances. The experimental average heat coefficients gives relatively low error of only 5% in case of double drop when compared to the single drop values.

Effect of adjuvants on the spray droplet size of pesticide dilute emulsion

Spray droplet size is an important factor affecting spray drift, which is directly related to the spray effect and efficiency by unmanned aerial vehicle. Effect of adjuvants on the droplet size of emamectin benzoate dilute emulsion was systematically investigated by measuring droplet size, dynamic surface tension, and rheology. The results showed that droplet size was independent of dynamic surface tension and viscosity, but was related to the viscoelastic property and strain. For the emulsions with N, N-dimethyldodecylamine-N-oxid (OA), polyalkoxylated butyl ether (LQ) and poly (vinyl alcohol) (PVA), the viscous modulus (G′′) were higher than elastic modulus (G′) under the crossover frequency, indicating that the emulsions were the viscous liquid. Furthermore, the diluted emulsions with OA and LQ had small drop, while that with PVA had big drop. These leaded to the breakup of the liquid sheet at lower deformation and the small spray droplet formation. While emulsions containing Guar gum 2-hydroxy-3-(trimethylammonio) propyl ether chloride (Gum Cl) and Sil800 (silicone adjuvant) exhibited a weak elastic behavior, and had the large droplet size. In addition, compared to the emulsions with OA, LQ and PVA, the dilute emulsions with Gum Cl and Sil800 had the large drop diameter, and G′ had a rapid decrease at bigger strain. This suggested the dilute emulsions with Gum Cl and Sil800 had a high stability during atomization. The study would provide a useful guide for selecting drift control adjuvants and raising pesticide efficiency.

Effect of molecular weight of Poly(ethylene glycol) on plasticization of Poly(ʟ-lactic acid)

Poly(ʟ-lactic acid) (PLLA) is a sustainable, biodegradable polymer, but the inherent brittleness impedes its potential application. In this study, we use poly(ethylene glycol) (PEG) to plasticize PLLA and systematically study the effect of molecular weight (MW) and content of PEG on the thermal and mechanical properties of PLLA/PEG blends. We observed a surprisingly big drop of elongation at break (εb = 32%) in PLLA/PEG5-15% where PEG5-15% represents 15 wt% of PEG with the MW of 5 kg/mol while εbs of PLLA/PEG-15% where PEG-15% represents 15 wt% of PEG with other MW PEGs were ~300%. WAXD results confirmed that PLLA in quenched PLLA/PEG-15% blends crystallized into mixtures of α′-form and α-form crystals during heating. DSC analysis showed that two cold crystallization temperature (Tccs) were observed in PLLA/PEG5-15% while only one Tcc was observed in PLLA/PEG2-15% and PLLA/PEG8-15%, indicating that PLLA/PEG5-15% formed separated α′-form and α-form crystals while the other two blends formed mixed α′-form and α-form crystals. The competition between phase separation and PLLA crystallization determined the final structures and physical properties of PLLA/PEG blends.

The Impact of the COVID-19 Pandemic on Ambient Air Quality in China: A Quasi-Difference-in-Difference Approach.

The novel coronavirus (COVID-19) pandemic has provided a distinct opportunity to explore the mechanisms by which human activities affect air quality and pollution emissions. We conduct a quasi-difference-in-differences (DID) analysis of the impacts of lockdown measures on air pollution during the first wave of the COVID-19 pandemic in China. Our study covers 367 cities from the beginning of the lockdown on 23 January 2020 until April 22, two weeks after the lockdown in the epicenter was lifted. Static and dynamic analysis of the average treatment effects on the treated is conducted for the air quality index (AQI) and six criteria pollutants. The results indicate that, first, on average, the AQI decreased by about 7%. However, it was still over the threshold set by the World Health Organization. Second, we detect heterogeneous changes in the level of different pollutants, which suggests heterogeneous impacts of the lockdown on human activities: carbon monoxide (CO) had the biggest drop, about 30%, and nitrogen dioxide (NO2) had the second-biggest drop, 20%. In contrast, ozone (O3) increased by 3.74% due to the changes in the NOx/VOCs caused by the decrease in NOx, the decrease of O3 titration, and particulate matter concentration. Third, air pollution levels rebounded immediately after the number of infections dropped, which indicates a swift recovery of human activities. This study provides insights into the implementation of environmental policies in China and other developing countries.

Suicides in the COVID-19 Pandemic - Are We Well Informed Regarding Current Risks and Future Prospects?

Suicides are predicted to drop in the acute phase of any crisis that poses a threat to the entire population, though data on this are inconsistent. A pandemic is the most severe global crisis one can imagine. There is an urgent need to identify objective trends in suicide rates across countries and populations in a real-time manner in order to be better informed regarding prospects and adaptation of preventive strategies. To evaluate suicidal behaviour in a metropolis immediately after the introduction of severe containment measures due to the pandemic. Cases of completed suicides in St. Petersburg were obtained from the local city Bureau of Forensic Medical Examinations for the period 1 January 2016 to 31 July 2020. Data were accurately collected and monthly frequencies per 100,000 of the population in April-May 2020 (introduction of the most severe stay at home measures) were compared with corresponding data from 2016-2019. Confidence intervals were calculated according to Wilson. Suicide frequencies in the population of St. Petersburg in April 2020 did not go up, in contrast, they were 30.3% lower than the average for the previous four years. The decrease in April was more pronounced in males than in females (36.3% and12.4%, respectively). When looking at age groups it was found that the biggest drop in suicides was in older males ( 55 years). In this group, suicide indices were 58.5% lower than average for the previous four years. However, in females, there was a 50% rise in suicides in June, while in young males (15-34 years) there was an 87.9% rise in May. Total number of suicides for the first half of 2020 was very close to the average seen in previous years. None of the registered changes were statistically significant. The analysis is preliminary and does not account for possible seasonality, however, we consider that the reduction in completed suicides immediately after crisis exposure deserves attention. It supports views that in the acute phase of the crisis, suicidal behaviour may decline, which may be quickly replaced by a rise. Such a rise in females and younger males points on possible risk groups and requires a response from society. More studies are needed to have a clearer picture of suicide dynamics in Russia during the different waves of the pandemic, and prevention should be prioritized regardless of the tendencies.