Original Variant Research Articles

Involvement of MicroRNAs in Regulation of Radioresistance of HeLa and DU145 Cells

Using the method of massively parallel sequencing, differential miRNA expression profiles in the original and radioresistant variants of HeLa and DU145 cell lines after radiation exposure at the dose of 4 Gy were obtained. Comparative analysis made it possible to identify a group of miRNAs aberrant expression of which reflected the changes in cell metabolism of radioresistant variants that remained across a number of cell generations as compared to the original ones. The obtained results suggest that the role of miRNAs is associated with the maintenance of functional interaction between DNA methyltransferases, Myc transcription factor, and PTEN phosphatase in regulating the activity of PI3K/AKT and MAPK/ERK signaling pathways. This may underlie differences in realization of radioresistance of HeLa and DU145 cells.

Averaged optical characteristics of an ensemble of metal nanoparticles

A theory for the averaged optical characteristics of an ensemble of metal nanoparticles with different shapes has been developed. The theory is applicable both for the nanoparticle size at which the optical conductivity of the particle is a scalar and for the nanoparticle size at which the optical conductivity should be considered as a tensor. The averaged characteristics were obtained taking into account the influence of nanoparticle shape on the depolarization coefficient and the components of the optical conductivity tensor. The dependences of magnetic absorption by a spheroidal metal nanoparticle on the ratio between its curvature radii and the angle between the spheroid symmetry axis and the magnetic field vector were derived and theoretically considered. An original variant of the distribution function for nanoparticle shapes, which is based on the combined application of the Gaussian and “hat” functions, was proposed and analyzed.

Contrastive analysis of the semantic relations of connectors in argumentative texts in English and Albanian

 Abstract The main purpose of this paper is the functional analysis and argumentation of text connectors as tools for implementation of the textual connectivity not only in the local but also global context. Given the comparative nature of this paper, we will be comparing typology and relationships expressed by the connectors in some of the argumentative texts published in the investigative journalism Project Syndicate network with their analogous versions translated into Albanian and published in the Kosovo daily newspaper Koha Ditore. Thus, the treatment of the relationships they express will be realized by analyzing the preservation of the typology of the connectors during the translation process from the original variants in the language in which they are translated, in our case in Albanian. Such processed data will provide answers related to the frequency of the connectors’ use, their means of realization, relations expressed according to the prevalence of connectors as well as their semantic, grammatical and functional equivalency.                 Keywords: Textual connectivity; connectors; typology of relationships; relative frequency; argumentative text

Features first translation confucian text “Lunyu” on russian language

This paper is about research of the manuscript “Book Sishu or Shang Lunyu, of Chinese confucianistic law. Translated by Jacob Volkov”. This manuscript is a first Russian translation of confucianistic “Analects”, made in the XVIIIth century. Reason of research was in learning of specifics of this translation. This research is based on comparative analyse of Volkovs translation with original version of “Analects”, compiled by Zhu Xi. It was explain, that there a lot of differences between Volkovs translation and original variant of “Analects”. There is a large possibility that J. Volkov translated “Analects” from unknown and, perhaps, lost version of this text.

Adaptive Electromagnetic Field Optimization Algorithm for the Solar Cell Parameter Identification Problem

Solar cell parameter identification problem (SCPIP) is one of the most studied optimization problems in the field of renewable energy since accurate estimation of model parameters plays an important role to increase their efficiency. The SCPIP is aimed at optimizing the performance of solar cells by estimating the best parameter values of the solar cells that produce an accurate approximation between the current vs. voltage (I−V) measurements. To solve the SCPIP efficiently, this paper introduces an adaptive variant of the electromagnetic field optimization (EFO) algorithm, named adaptive EFO (AEFO). The EFO simulates the attraction-repulsion mechanism between particles of electromagnets having different polarities. The main idea behind the EFO is to guide electromagnetic particles towards global optimum by the attraction-repulsion forces and the golden ratio. Distinct from the EFO, the AEFO searches the solution space with an adaptive search procedure. In the adaptive search strategy, the selection probability of a better solution is increased adaptively whereas the selection probability of worse solutions is reduced throughout the search progress. By employing the adaptive strategy, the AEFO is able to maintain the balance between exploration and exploitation more efficiently. Further, new boundary control and randomization procedures for the candidate electromagnets are presented. To identify the performance of the proposed algorithm, two different benchmark problems are taken into account in the computational studies. First, the AEFO is performed on global optimization benchmark functions and compared to the EFO. The efficiency of the AEFO is identified by statistical significance tests. Then, the AEFO is implemented on a well-known SCPIP benchmark problem set formed as a result of real-life physical experiments based on single- and double-diode models. To validate the performance of the AEFO on the SCPIP, extensive experiments are carried out, where the AEFO is tested against the original EFO, AEFO variants, and novel metaheuristic algorithms. Results of the computational studies reveal that the AEFO exhibits superior performance and outperforms other competitor algorithms.

Success-history based biology-inspired algorithms for global trajectory optimization

Biology-inspired algorithms are computationally efficient for real-parameter optimization. However, the search efficiency of such algorithms depends significantly on their ability in keeping the balance between exploration and exploitation when solving complex multimodal problems. A new technique for generating potential solutions in biology-inspired algorithms is proposed. The stated technique uses a historical memory of successful positions found by individuals to guide them in different directions, thereby improving their exploration and exploitation abilities. Thus, this paper describes the application of modified biology-inspired algorithms, namely the Firefly Algorithm, the Cuckoo Search Algorithm and the Bat Algorithm to global trajectory optimization problems. The problems are provided by the European Space Agency and represent trajectories of several well-known spacecraft, such as Cassini and Messenger. Firstly, modified versions of the listed heuristics as well as their original variants were evaluated on a set of various test functions. Then their performance was evaluated on two global trajectory optimization problems: Cassini-1 and Messenger. The experimental results obtained by them are presented and compared. It was established that success-history based position adaptation allows better solutions to be found with the same computational effort while solving complex real-world problems. Thus, the usefulness of the proposed position adaptation technique was demonstrated.

Functional Characterization of Glucocorticoid Receptor Variants Is Required to Avoid Misinterpretation of NGS Data.

Recent advances in genetic analysis technologies such as next-generation sequencing (NGS) have considerably increased the incidental discovery of genetic abnormalities. Six heterozygous missense mutations of the human glucocorticoid receptor (GR; encoded by the NR3C1 gene) have been identified in the context of genetic screening of endocrine pathologies. GR, a nuclear receptor, hormone-induced transcription factor, is involved in many physiological processes. Nevertheless, the pathogenic significance of incidentally discovered mutations remains obscure. The aim of this work was to characterize these variants by evaluating their functional impact on GR signaling. Six original GR variants, located in exon 2, led to amino acid substitutions of the N-terminal domain of GR (F65V, M86V, A229T, A304E, N374S, and R386Q), excluding mainly the activation function tau core 1 domain, the potential site of functional interaction with transcriptional coregulators. Transient cotransfection in HEK293T cells of mutated GR-expressing vectors and a luciferase reporter established dose-response curves for dexamethasone. This excluded any major transactivation abnormality of the mutated GRs (ligand concentration leading to 50% maximal transactivation capacity ≈ 0.2 nM), with maximal transactivation capacity identical to that of the wild-type (WT) GR and without modification of the potentiation of transcriptional coactivator steroid receptor coactivator 2 except in N374S. Moreover, protein expression of mutated GRs and their cytonuclear translocation studied by immunocytochemistry were almost unchanged compared with WT GR. These results underline the silent nature of these missense GR variants and call for cautious interpretation of the discovery of genetic incidentalomas by NGS in the absence of detailed characterization in order to appropriately assess their functional impact on a particular signaling pathway.

A new class of recombinant human albumin with multiple surface thiols exhibits stable conjugation and enhanced FcRn binding and blood circulation

Human serum albumin is an endogenous ligand transport protein whose long circulatory half-life is facilitated by engagement with the human cellular recycling neonatal Fc receptor (hFcRn). The single free thiol located at Cys-34 in domain I of albumin has been exploited for monoconjugation of drugs. In this work, we increased the drug-to-albumin ratio potential by engineering recombinant human albumin (rHSA) variants with varying hFcRn affinity to contain three free, conjugation-competent cysteines. Structural analysis was used to identify positions for cysteine introduction to maximize rHSA stability and formation of the conjugated product without affecting hFcRn binding. The thiol rHSA variants exhibited up to 95% monomeric stability over 24 months and retained hFcRn engagement compared with a WT unconjugated control demonstrated by Biolayer Interferometry. The additional cysteines were further introduced into a panel of rHSA variants engineered with different affinities for hFcRn. After conjugation with three Alexa Fluor 680 (AF680) fluorophores, hFcRn binding was similar to that of the original triple-thiol nonconjugated rHSA variants (0.88 and 0.25 μm for WT albumin with or without 3xAF680 respectively, and 0.04 and 0.02 μm for a high hFcRn-binding variant with or without 3xAF680, respectively). We also observed a 1.3-fold increase in the blood circulatory half-life of a high hFcRn-binding triple-thiol variant conjugated with AF680 (t½ = 22.4 h) compared with its WT counterpart (t½ = 17.3 h) in mice. Potential high drug-to-albumin ratios combined with high hFcRn engagement are attractive features of this new class of albumins that offer a paradigm shift for albumin-based drug delivery.

The co-transfer of plasmid-borne colistin-resistant genes mcr-1 and mcr-3.5, the carbapenemase gene blaNDM-5 and the 16S methylase gene rmtB from Escherichia coli

We found an unusual Escherichia coli strain with resistance to colistin, carbapenem and amikacin from sewage. We therefore characterized the strain and determined the co-transfer of the resistance determinants. Whole genome sequencing was performed using both Illumina HiSeq X10 and MinION sequencers. Short and long reads were subjected to de novo hybrid assembly. Sequence type, antimicrobial resistance genes and plasmid replicons were identified from the genome sequences. Phylogenetic analysis of all IncHI2 plasmids carrying mcr-1 available in GenBank was performed based on core genes. Conjugation experiments were performed. mcr-3.5 was cloned into E. coli DH5α. The strain belonged to ST410, a type with a global distribution. Two colistin-resistant genes, mcr-1.1 and mcr-3.5, a carbapenemase gene blaNDM-5, and a 16S methylase gene rmtB were identified on different plasmids of IncHI2(ST3)/IncN, IncP, IncX3 and IncFII, respectively. All of the four plasmids were self-transmissible and mcr-1.1, mcr-3.5, blaNDM-5 and rmtB were transferred together. mcr-1-carrying IncHI2 plasmids belonged to several sequence types with ST3 and ST4 being predominant. MIC of colistin (4 μg/ml) for DH5α containing mcr-3.5 was identical to that containing the original mcr-3 variant. In conclusion, carbapenem resistance, colistin resistance and high-level aminoglycoside resistance can be transferred together even when their encoding genes are not located on the same plasmid. The co-transfer of multiple clinically-important antimicrobial resistance represents a particular challenge for clinical treatment and infection control in healthcare settings. Isolates with resistance to both carbapenem and colistin are not restricted to a given sequence type but rather are diverse in clonal background, which warrants further surveillance. The amino acid substitutions of MCR-3.5 have not altered its activity against colistin.

Towards compact swarm intelligence: a new compact firefly optimisation technique

Firefly Algorithm (FA) is a recent and promising swarm intelligence algorithm. It is inspired by the modelling of brightness and attractiveness manifested by fireflies. Like other population-based algorithms, it presents the drawbacks of high computational cost and memory storage. This paper deals with this problem and introduces a compact firefly optimisation technique with minimal computational and memory requirements. So, we present four new variants of compact firefly algorithm that require only a minimal computational cost. The swarm is compacted and represented by a Probability of Density Function (PDF). This idea is inspired from compact evolutionary algorithms (cEAs). Two solutions of memory storage of the population are presented and analysed. The first is based on normal PDF and the second on uniform PDF. Furthermore, two versions of compact Levy-flight firefly algorithm (cLFA) are also introduced. This paper takes a step towards new compact swarm intelligence algorithms. The proposed algorithms are compared to the state-of-art of cEAs and two original variants of FA using IEEE CEC2014 functions. In addition, the proposed algorithms are used to realise an optimal swing-up movement of a humanoid robot hanging on a bar.

ЕКСПЕРИМЕНТАЛЬНІ ХУДОЖНІ СТРАТЕГІЇ С.Д. КРЖИЖАНОВСЬКОГО

The author of the article investigates original artistic heritage – experimental art strategies which are repre- sented in short stories by Sigizmund Krzhizhanovskiy. The article gives short biographical information about Krzhizhanovs- kiy as his popularity is growing. The author of short stories is famous for his omniscience talent. Researcher distinguishes such experimental artistic traits as creation of heroes, model of creation individual author’s myth about the world, synthesis of literature kind and sort. These traits are specificity of transitional type of thinking Krzhizhanovs- kiy’s. According to investigations of following scientists M.Epstein, M.Khrenov, Y.Lotman, V.Silantieva Krzhizhanovskiy was identified as prominent representative of transitional cultural period of XX-th century. Researcher demonstrates series of artistic traits which are similar for transitional cultural period of XX-th century and short stories by Krzhizhanovskiy: disintegration of holistic systems; variable and dynamic presentation about existence, world, beauty, true; model of chaosmos; active production new conceptions artistic model of existence and world, human and system of their relationship; eschatological tempers; plurality and multiplicity of worlds; actualization of mythopoetic art; intensification of playing experimental type. Experimental strategies of creating heroes are the next: reconsideration traditional cultural discourse, different meta- morphosis and transformations, using artistic principal of alienation (by V. Shklovsky), active functioning of body’s code, and artistic model of substitution for lifelike heroes. Krzhizhanovskiy experiments also with artistic coordinates of world: space and time (chronotope). Artistic world in short stories by Krzhizhanovskiy disintegrates, splits up and such situations are used for creating plurality and multiplicity of worlds and interworld, quasiworld after apocalypse. Synthesis of literature kind and sort is a bright trait of transitional type of thinking. Short stories by Krzhizhanovskiy show original variants of metric prose. Krzhizhanovskiy uses diversity of principals for rhythmization through all the levels of artistic text. Beside, the principals of musical rhythmization are widely used in short stories. Krzhizhanovskiy coded 23-d Appassionata by Beethoven in one of his short story. The author creates complicated superstructure of the text that confirms diversity of searches artistic synthesis and experimental poetic.

Findings Annihilator(s) via Fault Injection Attack (FIA) on Boolean Function of Grain v0

In developing stream cipher algorithms, Boolean function is one of vital elements. Attacks on LFSR-based stream cipher is the challenge for the cryptanalyst to get low-degree annihilator(s). In this paper, we proposed Fault Injection Attack (FIA) on Boolean function of Grain v0, which is the original variant of Grain family algorithm. Fault injection attack (FIA) is used on Boolean function of Grain v0 by replacing certain coefficient with value of one (1) which results in the generation of several injected Boolean functions. With these injected Boolean function, we proceed using HAO’s algorithm to find annihilator(s). As a result, we obtained several new annihilator(s) of Grain v0’s Boolean function. This new annihilator(s) will be utilized to launch algebraic attacks upon Grain v0.

Towards compact swarm intelligence: a new compact firefly optimisation technique

Firefly Algorithm (FA) is a recent and promising swarm intelligence algorithm. It is inspired by the modelling of brightness and attractiveness manifested by fireflies. Like other population-based algorithms, it presents the drawbacks of high computational cost and memory storage. This paper deals with this problem and introduces a compact firefly optimisation technique with minimal computational and memory requirements. So, we present four new variants of compact firefly algorithm that require only a minimal computational cost. The swarm is compacted and represented by a Probability of Density Function (PDF). This idea is inspired from compact evolutionary algorithms (cEAs). Two solutions of memory storage of the population are presented and analysed. The first is based on normal PDF and the second on uniform PDF. Furthermore, two versions of compact Lévy-flight firefly algorithm (cLFA) are also introduced. This paper takes a step towards new compact swarm intelligence algorithms. The proposed algorithms are compared to the state-of-art of cEAs and two original variants of FA using IEEE CEC2014 functions. In addition, the proposed algorithms are used to realise an optimal swing-up movement of a humanoid robot hanging on a bar.

Crimping Profile Optimization on the Air Spring Using Finite Element Method

Abstract Due to the fact that the requirements of the industry aim to improve the dynamics, the safety and the comfort during the use of the vehicles, it is recommended to use the finite element method for component quality optimization. The purpose of this paper is to provide an overview of the current state of analysis through the finite element method of the crimping process used to assemble air springs produced in the automotive industry. Starting from the prototype of an air spring, the researches are focused on the study of the assembly of the piston with the bellow and the crimping ring through the crimping process. After analysis with the finite element method and static tests, improvements were made to the piston, the results of the tests revealing an improvement as opposed the original variant of the piston.

Three-Dimensional Point Cloud Registration Based on Normal Vector Angle

The widespread use of three-dimensional laser scanning makes point cloud registration essential for model reconstruction. Although iterative closest point (ICP) is a widely used algorithm for automatic and accurate point cloud registration, the ICP algorithm is time-intensive and typically falls in local optima. We employ the normal vector angle of the 3D model and integrate a heuristic search into the ICP algorithm to improve its efficiency, especially while registering complex surfaces. We compare this improved ICP algorithm with the original ICP algorithm and variants of the algorithm in terms of convergence, robustness, and response from a poor initial cloud point position to verify that the proposed improvements outperform the conventional ICP algorithm in the three evaluated aspects when processing point clouds with complex surfaces.

Analysis of tweets to find the basis of popularity based on events semantic similarity

PurposeThe purpose of this paper is to propose and experiment a framework for analysing the tweets to find the basis of popularity of a person and extract the reasons supporting the popularity. Although the problem of analysing tweets to detect popular events and trends has recently attracted extensive research efforts, not much emphasis has been given to find out the reasons behind the popularity of a person based on tweets.Design/methodology/approachIn this paper, the authors introduce a framework to find out the reasons behind the popularity of a person based on the analysis of events and the evaluation of a Web-based semantic set similarity measure applied to tweets. The methodology uses the semantic similarity measure to group similar tweets in events. Although the tweets cannot contain identical hashtags, they can refer to a unique topic with equivalent or related terminology. A special data structure maintains event information, related keywords and statistics to extract the reasons supporting popularity.FindingsAn implementation of the algorithms has been experimented on a data set of 218,490 tweets from five different countries for popularity detection and reasons extraction. The experimental results are quite encouraging and consistent in determining the reasons behind popularity. The use of Web-based semantic similarity measure is based on statistics extracted from search engines, it allows to dynamically adapt the similarity values to the variation on the correlation of words depending on current social trends.Originality/valueTo the best of the authors’ knowledge, the proposed method for finding the reason of popularity in short messages is original. The semantic set similarity presented in the paper is an original asymmetric variant of a similarity scheme developed in the context of semantic image recognition.

Re-inspiring the genetic algorithm with multi-level selection theory: multi-level selection genetic algorithm

Genetic algorithms are integral to a range of applications. They utilise Darwin’s theory of evolution to find optimal solutions in large complex spaces such as engineering, to visualise the design space, artificial intelligence, for pattern classification, and financial modelling, improving predictions. Since the original genetic algorithm was developed, new theories have been proposed which are believed to be integral to the evolution of biological systems. However, genetic algorithm development has focused on mathematical or computational methods as the basis for improvements to the mechanisms, moving it away from its original evolutionary inspiration. There is a possibility that the new evolutionary mechanisms are vital to explain how biological systems developed but they are not being incorporated into the genetic algorithm; it is proposed that their inclusion may provide improved performance or interesting feedback to evolutionary theory. Multi-level selection is one example of an evolutionary theory that has not been successfully implemented into the genetic algorithm and these mechanisms are explored in this paper. The resulting multi-level selection genetic algorithm (MLSGA) is unique in that it has different reproduction mechanisms at each level and splits the fitness function between these mechanisms. There are two variants of this theory and these are compared with each other alongside a unified approach. This paper documents the behaviour of the two variants, which show a difference in behaviour especially in terms of the diversity of the population found between each generation. The multi-level selection 1 variant moves rapidly towards the optimal front but with a low diversity amongst its children. The multi-level selection 2 variant shows a slightly slower evolution speed but with a greater diversity of children. The unified selection exhibits a mixed behaviour between the original variants. The different performance of these variants can be utilised to provide specific solvers for different problem types when using the MLSGA methodology.

CHARACTERISTICS OF THE BAIKAL SUBTYPE OF TICK-BORNE ENCEPHALITIS VIRUS CIRCULATING IN EASTERN SIBERIA

Background. During the study of the genetic variability of the tick-borne encephalitis virus (TBEV) in Eastern Siberia, a group of 22 strains with a unique genetic structure significantly different from all known TBEV subtypes was identified. This TBEV variant was tentatively called “group 886”. Therefore, for this original TBEV variant it was necessary to study the genetic, biological properties of the “group 886” strains, clarify its TBEV taxonomic status, its range, evolutionary history, etc.Aim. The generalization of the currently available data on genetic and biological properties of TBEV “886” group.Materials and methods. The genetic structure of “group 886” strains was studied by the complex of molecular-genetic methods (MHNA, sequencing of fragments or the complete genome).Results. It was shown that “group 886” strains form a separate cluster on phylogenetic tree, and the level of genetic differences from other genotypes is more than 12 %. It was defined that this TBEV variant has its own area (Irkutsk region, Republic of Buryatia, Trans-Baikal region, Northern Mongolia). Its ecological connection with all links of the transmissive chain (ixodid ticks, small mammals, human), participation in human pathology, stability and duration of circulation in the Baikal region, individual evolutionary history were proved. Some phenotypic characteristics of the “group 886” strains were considered.Conclusion. The presented data testify to the validity of the “886 group” isolation as an independent genetic type. Taking into account the geographical distribution of this TBEV genotype, we propose to assign it the name “Baikal genotype/subtype”.

ECD4-Ig Variants That More Potently Neutralize HIV-1.

The human immunodeficiency virus type 1 (HIV-1) entry inhibitor eCD4-Ig is a fusion of CD4-Ig and a coreceptor-mimetic peptide. eCD4-Ig is markedly more potent than CD4-Ig, with neutralization efficiencies approaching those of HIV-1 broadly neutralizing antibodies (bNAbs). However, unlike bNAbs, eCD4-Ig neutralized all HIV-1, HIV-2, and simian immunodeficiency virus (SIV) isolates that it has been tested against, suggesting that it may be useful in clinical settings, where antibody escape is a concern. Here, we characterize three new eCD4-Ig variants, each with a different architecture and each utilizing D1.22, a stabilized form of CD4 domain 1. These variants were 10- to 20-fold more potent than our original eCD4-Ig variant, with a construct bearing four D1.22 domains (eD1.22-HL-Ig) exhibiting the greatest potency. However, this variant mediated less efficient antibody-dependent cell-mediated cytotoxicity (ADCC) activity than eCD4-Ig itself or several other eCD4-Ig variants, including the smallest variant (eD1.22-Ig). A variant with the same architecture as the original eCD4-Ig (eD1.22-D2-Ig) showed modestly higher thermal stability and best prevented the promotion of infection of CCR5-positive, CD4-negative cells. All three variants, and eCD4-Ig itself, mediated more efficient shedding of the HIV-1 envelope glycoprotein gp120 than did CD4-Ig. Finally, we show that only three D1.22 mutations contributed to the potency of eD1.22-D2-Ig and that introduction of these changes into eCD4-Ig resulted in a variant 9-fold more potent than eCD4-Ig and 2-fold more potent than eD1.22-D2-Ig. These studies will assist in developing eCD4-Ig variants with properties optimized for prophylaxis, therapy, and cure applications.IMPORTANCE HIV-1 bNAbs have properties different from those of antiretroviral compounds. Specifically, antibodies can enlist immune effector cells to eliminate infected cells, whereas antiretroviral compounds simply interfere with various steps in the viral life cycle. Unfortunately, HIV-1 is adept at evading antibody recognition, limiting the utility of antibodies as a treatment for HIV-1 infection or as part of an effort to eradicate latently infected cells. eCD4-Ig is an antibody-like entry inhibitor that closely mimics HIV-1's obligate receptors. eCD4-Ig appears to be qualitatively different from antibodies, since it neutralizes all HIV-1, HIV-2, and SIV isolates. Here, we characterize three new structurally distinct eCD4-Ig variants and show that each excels in a key property useful to prevent, treat, or cure an HIV-1 infection. For example, one variant neutralized HIV-1 most efficiently, while others best enlisted natural killer cells to eliminate infected cells. These observations will help generate eCD4-Ig variants optimized for different clinical applications.

We Can Be Heroes Trust and Resilience in Corrupted Economic Environments

We use an original variant of the standard trust game, in order to study the effect of corruption on trust and trustworthiness. In this game, both the trustor and the trustee know that part of the surplus they can generate may be captured by a third “corrupted” player under different expected costs of audit and prosecution. We find slightly higher trustor’s giving in presence of corruption, matched by a significant effect of excess reciprocity from the trustee. Both the trustor and the trustee expect on average corruption acting as a tax, inelastic to changes in the risk of corruptor audit. Expectations are correct for the inelasticity assumption, and for the actual value of the “corruption tax”. Our experimental findings lead to the rejection of four standard hypotheses based on purely self-regarding preferences. We discuss how the apparently paradoxical excess reciprocity effect is consistent with the cultural role of heroes in history where examples of commendable giving were used to stimulate emulation of the ordinary people. Our results suggest that the excess reciprocity component of the trustee makes trustor’s excess giving a rational and effective strategy.