[Polyphenols of natural origin against age-related disorders of tissue homeostasis.]

Aging-related disorders of tissue homeostasis may lead to excessive cell proliferation in the form of cancer and to extracellular matrix expansion in the form of fibroses. Death rates attributed to both of the conditions are decreased, according to epidemiological evidence, upon increased dietary intakes of polyphenols, including flavonoids, stilbenes, lignans, and curcuminoids. That is, polyphenols, although they have very different structures, unidirectionally influence the two opposite sides of balance in tissue homeostasis: the cells, which are able, and the extracellular matrix, which is unable to proliferate. The common features of fibroses and cancer are the transformation of fibroblasts into myofibroblasts (MF) and the epithelial- and endothelial-to-mesenchymal transitions (EMT and EndMT), which shift cell proportions in tissues toward MF. The increased ability of MF to produce collagen promotes fibroses in non-cancerous tissues, and EMT and EndMT enhance cancer progression. These processes are influenced by not polyphenols themselves due to their interactions with different sterically suitable targets, but by polyphenol oxidation products, which are all highly electrophilic. By binding to the SH-groups of the KEAP1 protein complexed with the NRF2 protein, they release NRF2, which is generally known as a transcription factor involved in activating the genes implicated in cell antioxidant defenses. In the present review, attention is drawn to the published data about NRF2 ability to attenuate TGFß1 signaling, which promotes fibroblasts conversion into MF and enhances EMP and EndMP, that is increases the phenotypic instability of cells. Thus, the anticarcinogenic and antifibrotic effects of polyphenols may both involve cell phenotype stabilization, which may contribute to the geroprotector effects of polyphenols.

Single-pass method for reconstruction of extreme UV spectra.

This work is devoted to the development of a method for the reconstruction of plasma extreme UV (EUV) spectra recorded by a three frame grazing incidence spectrograph (GIS-3D). The spectrograph provides registration of radiation reflected from the diffraction grating (DG) on a three-frame detector based on a microchannel plate with a scintillator screen and registration on a CCD camera, with an exposure time of one frame of ∼1.5 ns. DG has a gold-coated spherical concave form with a radius of curvature of 2 m and dimensions of 30 × 40 × 10 mm3. In this case, radiation is incident on the DG at a grazing angle of 2°; the DG period is 1.66 µm. The new single-pass method for the reconstruction of plasma EUV spectra was developed, which solves the inverse problem of decomposing experimental signals into separate contributions from each of the diffraction orders, followed by the reconstruction of the true plasma spectrum. Using the developed method, the possibility of finding a close approximation to the shape of a DG groove profile based on a priori information about the recorded spectra was demonstrated. In order to test and demonstrate the efficiency of this method, several experimental EUV spectra obtained at the Z-pinch facility Angara-5-1 with a current of ∼3-4 MA through loads made of either tungsten wires or polypropylene fibers were reconstructed. In addition, to test the single-pass method, the transmittance of EUV in cold aluminum was measured in the wavelength range of 3-35 nm, and it has a good match with the Henke database.

An underappreciated peculiarity of late-life human mortality kinetics assessed through the lens of a generalization of the Gompertz-Makeham law.

Much attention in biogerontology is paid to the deceleration of mortality rate increase with age by the end of a species-specific lifespan, e.g. after ca. 90 years in humans. Being analyzed based on the Gompertz law µ(t)=µ0e^γt with its inbuilt linearity of the dependency of lnµ on t, this is commonly assumed to reflect the heterogeneity of populations where the frailer subjects die out earlier thus increasing the proportions of those whose dying out is slower and leading to decreases in the demographic rates of aging. Using Human Mortality Database data related to France, Sweden and Japan in five periods 1920, 1950, 1980, 2018 and 2020 and to the cohorts born in 1920, it is shown by LOESS smoothing of the lnµ-vs-t plots and constructing the first derivatives of the results that the late-life deceleration of the life-table aging rate (LAR) is preceded by an acceleration. It starts at about 65 years and makes LAR at about 85 years to become 30% higher than it was before the acceleration. Thereafter, LAR decreases and reaches the pre-acceleration level at ca. 90 years. This peculiarity cannot be explained by the predominant dying out of frailer subjects at earlier ages. Its plausible explanation may be the acceleration of the biological aging in humans at ages above 65-70 years, which conspicuously coincide with retirement. The decelerated biological aging may therefore contribute to the subsequent late-life LAR deceleration. The biological implications of these findings are discussed in terms of a generalized Gompertz-Makeham law µ(t) = C(t)+µ0e^f(t).

The Effect of Inactivating Heterozygous Mutation in NBS1 Gene on DNA Damage and Repair Markers and Apoptosis Markers in Mice.

We studied the state of the DNA repair system and apoptosis in young mice carrying heterozygous inactivating mutation in the NBS1 gene (c.1971insT, p.Arg658Stop). In the peripheral blood cells of 4-month-old NBS1insT males, the %DNA in the comet tail was higher by 10% than in wild-type mice (wt) (p<0.05). In hepatocytes of NBS1insT mice, the proportion of γH2AX+ nuclear regions marking DNA double-strand breaks was lower by 2 times than in wt mice (p<0.05), which can be an indicator of less efficient DNA repair. In the kidney tissue of NBS1insT mice, a tendency towards the proapoptotic ratio of Bax and Bcl-2 protein markers was revealed against the background of their reduced expression. Thus, the disturbances detected NBS1insT mice in young age suggest that this model is promising for further studies of carcinogenesis.

Monitoring of the heavy-ion beam distribution using poly- and monochromatic x-ray fluorescence imaging.

In this work, the first proof of the principal of an in situ diagnostics of the heavy-ion beam intensity distribution in irradiation of solid targets is proposed. In this scheme, x-ray fluorescence that occurs in the interaction of heavy-ions with target atoms is used for imaging purposes. The x-ray conversion to optical radiation and a transport-system was developed, and its first test was performed in experiments at the Universal Linear Accelerator in Darmstadt, Germany. The Au-beam intensity distribution on thin foils and Cu-mesh targets was imaged using multiple x-ray pinholes (polychromatic imaging) and 2D monochromatic imaging of Cu Kα radiation by using a toroidally bent silicon crystal. The presented results are of importance for application in experiments on the investigation of the equation of states of high energy density matter using high intensity GeV/u heavy-ion beams of ≥1010 particles/100 ns.

[Features of the course of non-ST elevation myocardial infarction in patients with a history of COVID-19].

Aim      To study the clinical course of non-ST segment elevation myocardial infarction (NSTEMI) in hospitalized patients after COVID-19 and to evaluate the effect of baseline characteristics of patients on the risk of complications.Material and methods  The study included 209 patients with NSTEMI; 104 of them had had COVID-19. The course of myocardial infarction (MI) was analyzed at the hospital stage, including evaluation of the incidence rate of complications (fatal outcome, recurrent MI, life-threatening arrhythmias and conduction disorders, pulmonary edema, cardiogenic shock, ischemic stroke, gastrointestinal bleeding).Results Mean age of patients after COVID-19 was 61.8±12.2 years vs. 69.0±13.0 in the comparison group (p<0.0001). The groups were comparable by risk factors, clinical data, and severity of coronary damage. Among those who have had СOVID-19, there were fewer patients of the GRACE high risk group (55.8 % vs. 74.3 %; p<0.05). Convalescent COVID-19 patients had higher levels of C-reactive protein and troponin I (p<0.05). The groups did not significantly differ in the incidence of unfavorable NSTEMI course (p>0.05). However, effects of individual factors (postinfarction cardiosclerosis, atrial fibrillation, decreased SpO2, red blood cell concentration, increased plasma glucose) on the risk of complications were significantly greater for patients after COVID-19 than for the control group (p<0.05).Conclusion      Patients with NSTEMI, despite differences in clinical history and laboratory data, are characterized by a similar risk of death at the hospital stage, regardless of the past COVID-19. Despite the absence of statistically significant differences in the incidence of in-hospital complications, in general, post-COVID-19 patients showed a higher risk of complicated course of NSTEMI compared to patients who had not have COVID-19. In addition, for this category of patients, new factors were identified that previously did not exert a clinically significant effect on the incidence of complications: female gender, concentration of IgG to SARS-CoV-2 ≥200.0 U/l, concentration of С-reactive protein ≥40.0 mg/l, total protein <65 g/l. These results can be used for additional stratification of risk for cardiovascular complications in patients with MI and also for development of individual protocols for evaluation and management of NSTEMI patients with a history of COVID-19.

[The lifespans of scholars referred to different disciplines according to data from diverse sources: Inferences and challenges.]

Human lifespan is known to correlate positively with education level. In the present paper, it is explored whether there are significant differences in lifespan among those whose education may be reasonably rated as the highest possible, i.e. among scholars referred to different scientific disciplines. The publications where the lifespans of scholars were estimated against the general population are reviewed, and the estimates are compared with those derived from the Database of Persons Included in Encyclopedias (DBPE), which has been being developed by the authors since 2008 based on Wikipedia records. With all caveats associated with the peculiarities of the procedures of including biographic data in Wikipedia, the estimates derived from the latest version of DBPE correspond to earlier estimates and confirm the conclusions based on other data sources: scholars' mean age at death (MAD) and life expectancy (LE) steadily increased since the Medieval period up to the modern time, were higher than those of the general population, and where the highest among the scientific elite. An unexpected finding was that MAD and LE of economists were usually the highest, whereas those of the mathematicians were lowest compared with specialists in other research fields. The difference between the two extreme cases ranges from ca. 3 to 5 years in different historical periods. Further examination of the difference between the extremes may reveal what factors behind it may be at work generally, even though they manifest themselves less overtly in other cases.

[The forensic implications of the relationship between the proteolytic enzymes activity and the changes in NADH and FAD fluorescence intensity in skeletal muscle when determining the time of death (experimental study)]. / Sudebno-meditsinskoe znachenie vzaimosvyazi aktivnosti proteoliticheskikh fermentov i dinamiki intensivnosti fluorestsentsii kofermentov NADH i FAD v skeletnoi myshtse pri diagnostike davnosti nastupleniya smerti (eksperimental'noe issledovanie).

OBJECTIVE: Evaluation of the relationship between the activity of proteolytic enzymes (cathepsin D and calpains) and the dynamics of the fluorescence intensity of the coenzymes nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) in the rats' skeletal muscles in relation to the time of death. The proteolytic activity of enzymes in rat skeletal muscle was determined at the postmortem time points corresponding to the most significant changes in the dynamics of coenzymes NADH and FAD fluorescence intensity. The proteolytic enzymes activity was found to be low during the period of increasing intensity of NADH fluorescence observed within 3 hours after death. An increase in the activity of proteolytic enzymes was registered in 4.5 hours after death which corresponds to the initial point of decrease in NADH fluorescence intensity. In 24 hours post-mortem, corresponding to increased FAD fluorescence intensity a significant decrease in the activity of calpains was found. The results of the study suggest that the nature of the postmortem dynamics of the fluorescence intensity of coenzymes is largely due to the peculiarities of intracellular proteolysis. The study results suggest that the pattern of post mortem changes in coenzyme fluorescence intensity is largely attributable to the specifics of intracellular proteolysis. The relationship between coenzyme fluorescence and molecular mechanisms of cell death confirms the viability and feasibility of laser-induced spectroscopy for post-mortem changes assessment when determining the time of death.

Benchmark Experiment to Prove the Role of Projectile Excited States Upon the Ion Stopping in Plasmas.

We report on a precision energy loss measurement and theoretical investigation of 100 keV/u helium ions in a hydrogen-discharge plasma. Collision processes of helium ions with protons, free electrons, and hydrogen atoms are ideally suited for benchmarking plasma stopping-power models. Energy loss results of our experiments are significantly higher than the predictions of traditional effective charge models. We obtained good agreement with our data by solving rate equations, where in addition to the ground state, also excited electronic configurations were considered for the projectile ions. Hence, we demonstrate that excited projectile states, resulting from collisions, leading to capture-, ionization-, and radiative-decay processes, play an important role in the stopping process in plasma.

[Theory and practice of aging upon COVID-19 pandemic.]

Never before in history, aging was such a significant factor for epidemics as it is now for the current COVID-19 pandemic, which features a drastic shift of mortality towards older ages. Our analysis of data on COVID-19-related mortality in Spain, Italy, and Sweden has shown that, in the range of 30 to 90 years of age, each dependency of the logarithm of mortality upon age is linear, and all regression lines are strictly parallel to those related to the total mortality in accordance with the Gompertz law. In all cases, irrespective of the stage and place of epidemic, mortality doubling time in this age range is close to 7,5 years. The rates of being infected with the SARS-CoV-2 coronavirus and of being diagnosed due to the symptomatic manifestations of the infection are dependent on age to a far lesser degree. With account for these observations, three messages are put forth: 1) Older persons are the principal victims of both SARS-CoV-2 and measures undertaken to control its spread; 2) Older persons are not the principal driving force of SARS-CoV-2 spread; 3) Older persons can and should be engaged in combating the pandemic and its consequences; however, not via selective social distancing and other discriminative measures. People aged over 65 years constitute a significant part of the current population. They have specific interests and needs, which deserve no less respect than those of any other age group. This includes the right for the quality of life that remains sustained under the emergency conditions. Since the prospects for controlling the SARS-CoV-2 are dubious, those in charge of decisions concerning «people aged above 65¼ should mind that currently, unlike in the medieval ages, 65+ is the individual future of almost everyone.

In vitro Reconstitution of the S. aureus 30S Ribosomal Subunit and RbfA Factor Complex for Structural Studies.

Ribosome-binding factor A (RbfA) from Staphylococcus aureus is a cold adaptation protein that is required for the growth of pathogenic cells at low temperatures (10-15°C). RbfA is involved in the processing of 16S rRNA, as well as in the assembly and stabilization of the small 30S ribosomal subunit. Structural studies of the 30S-RbfA complex will help to better understand their interaction, the mechanism of such complexes, and the fundamental process such as 30S subunit assembly that determines and controls the overall level of protein biosynthesis. This article describes protocols for preparation of RbfA and the small 30S ribosomal subunits and reconstitution and optimization of the 30S-RbfA complex to obtain samples suitable for cryo-electron microscopy studies.

[Determination of the fluorescence intensity of coenzymes NADH and FAD in the skeletal muscle of the rat depending on the post-mortem interval]. / Opredelenie intensivnosti fluorestsentsii kofermentov NADN i FAD v skeletnoi myshtse krysy v zavisimosti ot davnosti nastupleniia smerti.

Aim of the study is to identify patterns of variations of the fluorescence intensity of NADH (reduced nicotinamide adenine dinucleotide) and FAD (oxidized flavin adenine dinucleotide) in the skeletal muscle depending on the time since death. For the evaluation of fluorescence intensity of the studied coenzymes, laser-induced spectroscopy in situ was used. We revealed the dynamic of the fluorescence intensity of NADH and FAD in the skeletal muscle of a rat at different times during the post-mortem period, and theoretically justified the observed phenomena. The results obtained allow us to consider the studied indicators as a potential criterion for determining the post-mortem interval.

[Comparative analysis of experimental data about the effects of various polyphenols on lifespan and aging.]

To analyze experimental data on the effect of various polyphenolic compounds on lifespan of mice, we approximated survival curves with the Gompertz model in its minimal form, which does not account for the heterogeneity of samples and the age-independent mortality. The plots of regressions of log0 (logarithm of the initial mortality) on  (the rate of aging) in series of control samples were used to assess the deviations of vectors directed from control to experimental data from the slopes of the control regressions. The analysis of published data suggests that resveratrol, polyphenol-containing grape skin extract, metformin, tocopherol, and the antioxidant SkQ1 do not produce changes beyond those possible upon comparing of different samples of a control population. The effect of the polyphenolic composition BP-C3 on female SHR mice is unique in being associated with a significant decrease in the rate of aging. The effect may be partly contributed to by the antioxidant properties of BP-C3. Its antioxidant capacity determined in vitro is comparable with that of established antioxidants, such as dihydroquercetin. Its effects in vivo include the ability to ameliorate reduction in the peroxide-decomposing activity of RBC lysates from male BALB/c mice treated with 5-fluorouracil.

[Elongation Factor P: New Mechanisms of Function and an Evolutionary Diversity of Translation Regulation].

The protein synthesis in cells occurs in ribosomes, with the involvement of protein translational factors. One of these translational factors is the elongation factor P (EF-P). EF-P is a three-domain protein that binds between the P and E sites of the ribosome, near the P-tRNA, the peptidyl transferase center, and E-site codon of the mRNA. The majority of studies showed that the EF-P helps the ribosome to synthesize stalling amino acid motifs, such as polyprolines. In the first part of this review, we inspect the general evolutionary variety of the EF-P in different organisms, the problems of the regulation provided by the EF-P, and its role in the sustainability of the protein balance in the cell in different physiological states. Although the functions of the EF-P have been well studied, there are still some problems that remain to be solved. The data from recent studies contradict the previous theories. Consequently, in the second part, we discuss the recent data that suggest the involvement of the EF-P in each translocation event, not only in those related to poly-proline synthesis. This activity contradicts some aspects of the known pathway of the removal of the E-tRNA during the translocation event. In addition, in the third part of this review, we tried to partly shift the interest from the antistalling activity of domain I of the EF-P to the action of domain III, the functions of which has not been closely studied. We expand on the idea about the involvement of domain III of the EF-P in preventing the frameshift and debate the EF-P's evolutionary history.

A 2D analysis of correlations between the parameters of the Gompertz-Makeham model (or law?) of relationships between aging, mortality, and longevity.

When mortality (µ), aging rate (γ) and age (t) are treated according to the Gompertz model µ(t) = µ0eγt (GM), any mean age corresponds to a manifold of paired reciprocally changing µ0 and γ. Therefore, any noisiness of data used to derive GM parameters makes them negatively correlated. Besides this artifactual factor of the Strehler-Mildvan correlation (SMC), other factors emerge when the age-independent mortality C modifies survival according to the Gompertz-Makeham model µ(t) = C+µ0eγt (GMM), or body resources are partitioned between survival and protection from aging [the compensation effect of mortality (CEM)]. Theoretical curves in (γ, logµ0) coordinates show how µ0 decreases when γ increases upon a constant mean age. Within a species-specific range of γ, such "isoage" curves look as nearly parallel straight lines. The slopes of lines constructed by applying GM to survival curves modeled according to GMM upon changes in C are greater than the isoage slopes. When CEM is modeled, the slopes are still greater. Based on these observations, CEM is shown to contribute to SMC associated with sex differences in lifespan, with the effects of several life-extending drugs, and with recent trends in survival/mortality patterns in high-life-expectancy countries; whereas changes in C underlie differences between even high-life-expectancy countries, not only between high- and low-life-expectancy countries. Such interpretations make sense only if GM is not merely a statistical model, but rather reflects biological realities. Therefore, GM is discussed as derivable by applying certain constraints to a natural law termed the generalized Gompertz-Makeham law.

[Gender-specific effects of neonatal administration of melatonin on lifespan and age-associated patholgy in 129/Sv mice.]

Melatonin was administered at the dose of 1,2 mcg per capita (an equivalent to pediatric dosages) at days 1, 3 and 5 postpartum to 129/Sv mice, which were followed thereafter till their natural deaths. In adult males, findings included a decrease in body weight and an increase in the contribution of pulmonary lesions, which were revealed upon postmortem examinations, to the overall mortality. In adult females, no changes in body weight occurred, the proportion of middle- and late-age mice having irregular estrous cycles increased, and mortality associated with uterine hemangiomas was accelerated. Trends in malignant tumor yields were different: a decrease in males and an increase in females. Tends in survival patterns were expressed as significant increases or decreases in the lifespans of the last 25% and 10% of male or female survivors respectively. An analysis of the complete survivorships curves in terms of the Gompertz model showed that changes in the initial mortality and aging rate were within the limits determined by the artifactual component of the Strehler-Mildvan correlation between these parameters. On a whole, the trends found in the present work were opposite in males and females being mostly favorable for the former and adverse for the latter. Gender specificity should be kept in mind upon considering the use of melatonin by children and their mothers.

Dynamics of supernova bounce in laboratory.

We draw attention to recent high-explosive (HE) experiments which provide compression of macroscopic amount of matter to high, even record, values of pressure in comparison with other HE experiments. The observed bounce after the compression corresponds to processes in core-collapse supernova explosions after neutrino trapping. Conditions provided in the experiments resemble those in core-collapse supernovae, permitting their use for laboratory astrophysics. A unique feature of the experiments is compression at low entropy. The values of specific entropy are close to those obtained in numerical simulations during the process of collapse in supernova explosions, and much lower than those obtained at laser ignition facilities, another type of high-compression experiment. Both in supernovae and HE experiments the bounce occurs at low entropy, so the HE experiments provide a new platform to realize some supernova collapse effects in laboratory, especially to study hydrodynamics of collapsing flows and the bounce. Due to the good resolution of diagnostics in the compression of macroscopic amounts of material with essential effects of nonideal plasma in EOS, and observed development of 3D instabilities, these experiments may serve as a useful benchmark for astrophysical hydrodynamic codes.

[Why and how do we age? - a single answer to the two questions.]

The chemical properties of compounds involved in metabolic processes, even the core ones, such as glycolysis and Krebs cycle, are not limited to what is realized via enzymatic reactions, because the properties include the abilities to form spontaneousely covalent bonds with other compounds, incuding those incorporated in macromolecules. The effects of the gene that codes for an enzyme, which catalizes the formation of a metabolite, which features such extra properties, may be regarded as antagonistically pleiotropic. The effects that are realized via the product of the reaction catalysed by the enzyme coded by a gene are required for current viability. The effects that are mediated by the spontaneous formation of covalent bonds between the same product and slowly renewable macromolecules will be increasingly deleterious with increasing time of their accumulation provided by the positive effects. Thus, the antagonistically pleiotripic effects are not late-acting, as it is commonly believed, but rather they are cumulative. Since these effects are inseparable from metabolism, they may be labeled "parametabolic". The driving force produced by these effects is sufficient for aging to take place in any system that exists due to metabolic processes therein and proliferate due to information stored by components featuring much slower turnover compared with that of metabolites. Thus, we age because of the chemical properties of our constituents and do it so as it is determined by these properies realized within conditions of our bodies. Aging is neither a direct product of evolution (such as a program that determines the span of life), nor a byproduct (a delayed payment for current advantages). Aging results from limitations that the immanent physicochemical properties of metabolites impose on the capabilities and outcomes of evolution by natural selection, and this is what distinguishes aging from the tear and wear of inanimate objects.

[Where does the Preston curve lead us?]

World Bank and Russian Federal State Statistics Service data were used to analyze cross-country correlations between life expectancy (LE) and per capita gross domestic product (pcGDP). The resulting world trend (Preston curve) as of 2015 was compared with the trend revealed by plotting regional LE vs. pcGDP related to the major administrative areas of the Russian Federation (RF). Besides that, correlations between the same parameters related to different years, from 1960 to 2015, were examined in each of several selected countries representing the upper and lower extremes of pcGDP and LE. The same has been done with per capita health care expenditures (pcHCE) vs. LE. In all cases, the points related to RF are found significantly lower the respective regression lines (Preston curves) built based on all points. The LE vs. pcGDP and LE vs. pcHCE plots and their extrapolations built based on data related to different years in the same country run markedly lower in the case of RF compared with other countries, including Tajikistan and the Republic of Congo. At the same time, the proportion between pcGDP and pcHCE has been shown to be the same throughout all years and all countries. Taken together, these observations suggest that the effectiveness of investing the available resources into LE, that is in human life quality, is markedly lower in Russia compared not only with Finland and Japan, where pcGDP and pcHCE are several times greater than in RF, but also with Congo and Tajikistan, where these parameters are several fold smaller, than in RF. This means that by merely increasing pcGDP and pcHCE it is impossible to increase LE in Russia above 80 years declared a national priority. Identifying the factors responsible for the above disproportions is beyond the scope of the present paper. However, the mere awareness of their existence is essential as an incentive to take special efforts aimed at the identification and neutralization of these factors.

Exponentially Modified Peak Functions in Biomedical Sciences and Related Disciplines.

In many cases relevant to biomedicine, a variable time, which features a certain distribution, is required for objects of interest to pass from an initial to an intermediate state, out of which they exit at random to a final state. In such cases, the distribution of variable times between exiting the initial and entering the final state must conform to the convolution of the first distribution and a negative exponential distribution. A common example is the exponentially modified Gaussian (EMG), which is widely used in chromatography for peak analysis and is long known as ex-Gaussian in psychophysiology, where it is applied to times from stimulus to response. In molecular and cell biology, EMG, compared with commonly used simple distributions, such as lognormal, gamma, and Wald, provides better fits to the variabilities of times between consecutive cell divisions and transcriptional bursts and has more straightforwardly interpreted parameters. However, since the range of definition of the Gaussian component of EMG is unlimited, data approximation with EMG may extend to the negative domain. This extension may seem negligible when the coefficient of variance of the Gaussian component is small but becomes considerable when the coefficient increases. Therefore, although in many cases an EMG may be an acceptable approximation of data, an exponentially modified nonnegative peak function, such as gamma-distribution, can make more sense in physical terms. In the present short review, EMG and exponentially modified gamma-distribution (EMGD) are discussed with regard to their applicability to data on cell cycle, gene expression, physiological responses to stimuli, and other cases, some of which may be interpreted as decision-making. In practical fitting terms, EMG and EMGD are equivalent in outperforming other functions; however, when the coefficient of variance of the Gaussian component of EMG is greater than ca. 0.4, EMGD is preferable.