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Developing humor competence in a second or foreign language is difficult, but it is very important for successful intercultural communication. The nature of humor and its sociocultural functions make humor competence one of the last hurdles even advanced language learners often struggle to overcome. Since types of humor and attitudes towards joking are different in different cultures and humor comprehension requires a complex combination of linguistic and cultural knowledge, second or foreign language teachers need to help their students with this often-neglected area of pragmatics. In social, academic, and professional settings, humor can relieve tension, exert social control, and enhance social cohesion, delineating who belongs or does not belong in a particular group. As humor can function both as a cultural divide and a unifying factor, the time has come to include some type of humor competency training in second or foreign language education. Based on humor research and research in teaching English as a second or foreign language, more and more educators are beginning to experiment with, document, and evaluate the results of various strategies and approaches to teaching with and about humor in English.

Every heartbeat is generated by spontaneously depolarizing specialised nodal cells that make up the sinoatrial node (SN). The SN's unique properties depend on two complex mechanisms - the membrane-voltage and the Ca2+ clocks, regulated by strictly defined expression of ion channels, connexins and Ca2+-handling proteins. In the working myocardium these proteins are accumulated in specialised membrane structures– the transverse tubules (t-tubules). It is well known that small mammals do not exhibit t-tubules in their atrium, but such structures are observed in the atria of bigger mammals such as sheep. No information on t-tubules in the human SN is present yet. The aim of our study was to determine if t-tubules are present in the human SN, as well as surrounding atrial myocardium. Dystrophin (cytoplasmic protein connecting the muscle fibres to the surrounding extracellular membrane), Na+-Ca2+ exchanger (NCX1), sarcoplasmic-endoplasmic reticulum calcium adenosine triphosphatase (SERCA2a), α-actinin, and ryanodine receptor 2 (RyR2) were investigated. Staining with wheat germ agglutinin (WGA, specific marker of t-tubules) demonstrated that human RA cells contain t-tubules, but these structures are very sparse in the SN. Experiments in single nodal cells from rat and mouse showed no expression of t-tubular network, but striated pattern of expression of RyR2 was obtained similar to the human sections, suggesting its manner of organization is dependent on α-actinin colocalization.

RESEARCH PURPOSE: The sinus node (SN) is the heart's primary pacemaker. Key ion channels (mainly the funny channel, HCN4) and Ca2+-handling proteins in the SN are responsible for its function. Transcription factors (TFs) regulate gene expression through inhibition or activation and microRNAs (miRs) do this through inhibition. There is high expression of macrophages and mast cells within the SN connective tissue. 'Novel'/unexplored TFs and miRs in the regulation of ion channels and immune cells in the SN are not well understood. Using RNAseq and bioinformatics, the expression profile and predicted interaction of key TFs and cell markers with key miRs in the adult human SN vs. right atrial tissue (RA) were determined.PRINCIPAL RESULTS: 68 and 60 TFs significantly more or less expressed in the SN vs. RA respectively. Among those more expressed were ISL1 and TBX3 (involved in embryonic development of the SN) and 'novel' RUNX1-2, CEBPA, GLI1-2 and SOX2. These TFs were predicted to regulate HCN4 expression in the SN. Markers for different cells: fibroblasts (COL1A1), fat (FABP4), macrophages (CSF1R and CD209), natural killer (GZMA) and mast (TPSAB1) were significantly more expressed in the SN vs. RA. Interestingly, RUNX1-3, CEBPA and GLI1 also regulate expression of these cells. MiR-486-3p inhibits HCN4 and markers involved in immune response.MAJOR CONCLUSIONS: In conclusion, RUNX1-2, CSF1R, TPSAB1, COL1A1 and HCN4 are highly expressed in the SN but not miR-486-3p. Their complex interactions can be used to treat SN dysfunction such as bradycardia. Interestingly, another research group recently reported miR-486-3p is upregulated in blood samples from severe COVID-19 patients who suffer from bradycardia.

Mir-133a-3p is the most abundant myocardial microRNA. The impact of mir-133a-3p on cardiac electrophysiology is poorly explored. In this study, we investigated the effects of mir-133a-3p on the main ionic currents critical for action potential (AP) generation and electrical activity of the heart. We used conventional ECG, sharp microelectrodes and patch-clamp to clarify a role of mir-133a-3p in normal cardiac electrophysiology in rats after in vivo and in vitro transfection. Mir-133a-3p caused no changes to pacemaker APs and automaticity in the sinoatrial node. No significant changes in heart rate (HR) were observed in vivo; however, miR transfection facilitated HR increase in response to β-adrenergic stimulation. Mir-133a-3p induced repolarization abnormalities in the atrial working myocardium and the L-type calcium current (ICa,L) was significantly increased. The main repolarization currents, including the transient outward (Ito), ultra-rapid (IK,ur), and inward rectifier (IK1) remained unaffected in atrial cardiomyocytes. Mir-133a-3p affected both ICa,L and Ito in ventricular cardiomyocytes. Systemic administration of mir-133a-3p induced QT-interval prolongation. Bioinformatic analysis revealed protein phosphatase 2 (PPP2CA/B) and Kcnd3 (encoding Kv4.3 channels generating Ito) as the main miR-133a-3p targets in the heart. No changes in mRNA expression of Cacna1c (encoding Cav1.2 channels generating ICa,L) and Kcnd3 were seen in mir-133a-3p treated rats. However, the expression of Ppp2cA, encoding PPP2CA, and Kcnip2 encoding KChIP2, a Kv4.3 regulatory protein, were significantly decreased. The accumulation of mir-133a-3p in cardiac myocytes causes chamber-specific electrophysiological changes. The suppression of PPP2CA, involved in adrenergic signal transduction, and Kchip2 may indirectly mediate mir-133a-3p-induced augmentation of ICa,L and attenuation of Ito.

Mir-133a-3p is the most abundant myocardial microRNA. The impact of mir-133a-3p on cardiac electrophysiology is poorly explored. In this study, we investigated the effects of mir-133a-3p on the main ionic currents critical for action potential (AP) generation and electrical activity of the heart. We used conventional ECG, sharp microelectrodes and patch-clamp to clarify a role of mir-133a-3p in normal cardiac electrophysiology in rats after in vivo and in vitro transfection. Mir-133a-3p caused no changes to pacemaker APs and automaticity in the sinoatrial node. No significant changes in heart rate (HR) were observed in vivo; however, miR transfection facilitated HR increase in response to β-adrenergic stimulation. Mir-133a-3p induced repolarization abnormalities in the atrial working myocardium and the L-type calcium current (I

Background The sinus node (SN) is the primary pacemaker of the heart. SN myocytes possess distinctive action potential morphology with spontaneous diastolic depolarization because of a unique expression of ion channels and Ca 2+ ‐handling proteins. MicroRNAs (miRs) inhibit gene expression. The role of miRs in controlling the expression of genes responsible for human SN pacemaking and conduction has not been explored. The aim of this study was to determine miR expression profile of the human SN as compared with that of non‐pacemaker atrial muscle. Methods and Results SN and atrial muscle biopsies were obtained from donor or post‐mortem hearts (n=10), histology/immunolabeling were used to characterize the tissues, TaqMan Human MicroRNA Arrays were used to measure 754 miRs, Ingenuity Pathway Analysis was used to identify miRs controlling SN pacemaker gene expression. Eighteen miRs were significantly more and 48 significantly less abundant in the SN than atrial muscle. The most interesting miR was miR‐486‐3p predicted to inhibit expression of pacemaking channels: HCN1 (hyperpolarization‐activated cyclic nucleotide‐gated 1), HCN4, voltage‐gated calcium channel (Ca v )1.3, and Ca v 3.1. A luciferase reporter gene assay confirmed that miR‐486‐3p can control HCN4 expression via its 3′ untranslated region. In ex vivo SN preparations, transfection with miR‐486‐3p reduced the beating rate by ≈35±5% ( P P Conclusions The human SN possesses a unique pattern of expression of miRs predicted to target functionally important genes. miR‐486‐3p has an important role in SN pacemaker activity by targeting HCN4, making it a potential target for therapeutic treatment of SN disease such as sinus tachycardia.

Bradyarrhythmias are an important cause of mortality in heart failure and previous studies indicate a mechanistic role for electrical remodelling of the key pacemaking ion channel HCN4 in this process. Here we show that, in a mouse model of heart failure in which there is sinus bradycardia, there is upregulation of a microRNA (miR-370-3p), downregulation of the pacemaker ion channel, HCN4, and downregulation of the corresponding ionic current, If, in the sinus node. In vitro, exogenous miR-370-3p inhibits HCN4 mRNA and causes downregulation of HCN4 protein, downregulation of If, and bradycardia in the isolated sinus node. In vivo, intraperitoneal injection of an antimiR to miR-370-3p into heart failure mice silences miR-370-3p and restores HCN4 mRNA and protein and If in the sinus node and blunts the sinus bradycardia. In addition, it partially restores ventricular function and reduces mortality. This represents a novel approach to heart failure treatment.

Functional properties of the sinoatrial node (SAN) are known to differ between sexes. Women have higher resting and intrinsic heart rates. Sex determines the risk of developing certain arrhythmias such as sick sinus syndrome, which occur more often in women. We believe that a major contributor to these differences is in gender specific ion channel expression.qPCR was used to compare ion channel gene expression in the SAN and right atrium (RA) between male and female rats. Histology, immunohistochemistry and signal intensity analysis were used to locate the SAN and determine abundance of ion channels. The effect of nifedipine on extracellular potential recording was used to determine differences in beating rate between sexes.mRNAs for Cav1.3, Kir3.1, and Nkx2-5, as well as expression of the L-Type Ca²⁺ channel protein, were higher in the female SAN. Females had significantly higher intrinsic heart rates and the effect of nifedipine on isolated SAN preparations was significantly greater in male SAN. Computer modelling using a SAN cell model demonstrated a higher propensity of pacemaker-related arrhythmias in females.This study has identified key differences in the expression of Cav1.3, Kir3.1 and Nkx2-5 at mRNA and/or protein levels between male and female SAN. Cav1.3 plays an important role in the pacemaker function of the SAN, therefore the higher intrinsic heart rate of the female SAN could be caused by the higher expression of Cav1.3. The differences identified in this study advance our understanding of sex differences in cardiac electrophysiology and arrhythmias.

Non-thermal atmospheric pressure plasmas are known to be an effective method for the inactivation of microorganisms. However, yeasts have proved to be more resistant to provided treatments. We investigated the influence of an Argon plasma jet on the inactivation of four different yeasts; Saccharomyces cerevisiae, Schizosaccharomyces pombe, Candida parapsilosis and Magnusiomyces magnusii. Results from direct plasma treatment on the yeasts in distilled water, as the most effective technique we found, are presented here. The surviving yeasts after 5, 7, and 10 min plasma exposures were evaluated visually and quantitatively. Quantitative results showed strong reductions in the survival rates after the plasma treatment. The longest plasma exposure time yielded the least survival. Moreover, how long the inactivations lasted was evaluated by assessing the treated samples after 1 h and again after 2 h. The survival rates were further decreased within these storage times. In the 10 min treated-2 h stored samples, the rates dropped to 5% or even below, depending on the yeast species. High concentrations of reactive oxygen and nitrogen species in the plasma-air-water interacting system were detected by optical emission spectroscopy of the plasma jet and also by measuring concentrations of H2O2, NO2 − and NO3 − in plasma activated water (as the surrounding liquid for the yeasts). The conductivity and pH of the treated water was measured as well. The level of the conductivity increased along with the decrease in pH. Synergistic effects of these chemical reactive species in acidified water resulted in the yeast inactivation.

Extracellular matrix remodelling is a key component of myocardial repair after ischaemic injury, and contributes to fibrotic changes leading to heart failure. MicroRNAs, short non-coding RNAs which regulate gene expression, have been shown to be dysregulated in a number of rodent models of ischaemia and heart failure, yet limited data is available in large translational animal models. The expression of a number of fibrosis-associated microRNAs were investigated in a relevant porcine model of mild to moderate left ventricular (LV) dysfunction induced by coronary microembolisation (n=3 MI and n=3 control pigs). Samples of myocardial tissue were obtained 4 weeks post-MI and classified into infarct, border and remote (normal) regions. The infarct area was histologically mostly acellular with dense inflammatory infiltrate, extracellular matrix expansion and collagen deposition as seen with Masson’s trichrome and Picrosirius red staining. qRT-PCR analysis of microRNA expression demonstrated downregulation of miR-133a (p=0.0085), whereas miR-214 was upregulated (p=0.0027) in the infarct region, compared to normal/control myocardium. miR-133a has previously been shown to protect against cardiac fibrosis, and is downregulated in the heart in numerous small-animal models of heart failure. miR-214 is upregulated in the fibrotic heart, and its inhibition has been shown to be protective against hepatic fibrosis. Therefore, our porcine data supports the hypothesis that pathological myocardial remodelling may be influenced by altered expression of microRNAs, and confirms the pattern of microRNA expression observed in other species. Future work is aimed at testing therapeutic approaches targeting these specific microRNAs.

Background: Heart failure (HF), a leading cause of morbidity and mortality, involves significant dysfunction of the sinoatrial node (SAN). MicroRNAs (miRs) are abundant, non-coding RNAs that ultimately regulate protein expression at the post-transcriptional level and have been implicated in HF. However, nothing is known about the distribution and expression of miRs in the human SAN as well as their roles in regulating pacemaker channels and SAN dysfunction (SND) in HF. Methods: The human SAN was isolated and cryopreserved from failing hearts with implantable pacemakers (n=5) or non-diseased donor hearts (n=3) that were cardioplegically arrested in the surgery room. Utilizing immunohistochemistry, the intact 3D intramural SAN structure was precisely identified as the fibrotic region around the SAN artery containing Connexin43-negative pacemaker cardiomyocytes (Figure). Small biopsies from the central SAN compartment were used to characterize the expression pattern of 14 miRs and their associated pacemaker channels. Ingenuity software (Qiagen) was used to predict the relationship between miRs and their targeted mRNA of SAN ion channels Results: Out of 14 studied miRs, 3 miRs (mir-370-3p miR-133-3a and miR-1) were significantly upregulated in SAN, but not in atria, during HF. We found that mir-370-3p was predominantly expressed in the human SAN, but not atria. Whereas, both miR-133-3a and miR-1 were highly expressed in atria vs SAN. All three miRs were predicted to regulate pacemaker HCN1 and/or HCN4 channel expression. RT-PCR showed that HCN1 and HCN4 mRNA were downregulated in the HF SAN. Conclusions: This is the first study to explore the miRs profiles in healthy and diseased human SAN with SND. We demonstrate that miR-370, miR-133a and miR-1, thought to regulate SAN pacemaker HCN channel expression, are selectively upregulated in human HF SAN. We propose that understanding the function of miRs in human SAN might lead to novel SND treatments.

In this paper we give a realization of the Shimura curve for the quaternion algebra over Q with discriminant 6 as a quotient space of the complex upper half plane by the triangle group Δ(3, 6, 6). It is given by the Schwarz map for the Gauss hypergeometric differential equation \({E\left(\frac{1}{6},\frac{1}{3},\frac{2}{3}\right)}\). The corresponding abelian surfaces are obtained as isogenous components of the Jacobi varieties of the Picard curves \({C(s): w^3=z(z-1)\break \left(z-\frac{1}{2} (1-s)\right)\left(z-\frac{1}{2} (1+s)\right)}\).

Background— Heart block is associated with pulmonary hypertension, and the aim of the study was to test the hypothesis that the heart block is the result of a change in the ion channel transcriptome of the atrioventricular (AV) node. Methods and Results— The most commonly used animal model of pulmonary hypertension, the monocrotaline-injected rat, was used. The functional consequences of monocrotaline injection were determined by echocardiography, ECG recording, and electrophysiological experiments on the Langendorff-perfused heart and isolated AV node. The ion channel transcriptome was measured by quantitative PCR, and biophysically detailed computer modeling was used to explore the changes observed. After monocrotaline injection, echocardiography revealed the pattern of pulmonary artery blood flow characteristic of pulmonary hypertension and right-sided hypertrophy and failure; the Langendorff-perfused heart and isolated AV node revealed dysfunction of the AV node (eg, 50% incidence of heart block in isolated AV node); and quantitative PCR revealed a widespread downregulation of ion channel and related genes in the AV node (eg, >50% downregulation of Ca v 1.2/3 and HCN1/2/4 channels). Computer modeling predicted that the changes in the transcriptome if translated into protein and function would result in heart block. Conclusions— Pulmonary hypertension results in a derangement of the ion channel transcriptome in the AV node, and this is the likely cause of AV node dysfunction in this disease.

Introduction: The sinoatrial node (SAN) is the primary pacemaker of the heart. Clinical evidence shows that SAN function differs between sexes. Males have slower resting (extrinsic and intrinsic) heart rates, and longer corrected SAN recovery time compared with females. Hypothesis: Sex based differences may be due to SAN ion channel differences. Therefore, we investigated functional behaviour and molecular makeup of SANs in male and female rats. Methods: Intracellular action potential recordings were obtained using sharp microelectrode technique (n=5 each). Gene expression was measured with quantitative PCR (n=6 each). Results: The amplitude of the action potential was significantly higher in male SANs (45.3 ± 2.4) compared with female (31.7 ± 2.5). The upstroke velocity (dV/dtmax) was significantly faster in female SANs (16.4 ± 1.6) compared with male (9.1 ± 1.5). Out of 96 transcripts investigated, two were significantly different between the sexes. L-Type Ca2+ channel, Cav1.3, and acetylcholine activated K+ channel, Kir3.1, mRNA levels were significantly higher in female SANs (66.6% and 45.6% respectively) compared with male. Immunolabelling for Cav1.3 showed levels were significantly higher in female SANs compared with male (18.6%, n=6 each). Inhibition of Cav1.3 with nifedipine (5μM) showed greater effect on the beating rate of male SANs compared with female (43%). A non-coding RNA, miR-139-3p (predicted by Ingenuity IPA software to affect Cav1.3) showed greater effect on the beating rate of male SAN preparations compared with female. Mathematical modelling showed that a higher density of Cav1.3 (as in the case of females) has a protective role from sinoatrial node arrhythmias. Conclusion: This study identified functional and molecular differences in key pacemaker ion channels in SAN between sexes. These differences advance our understanding of gender differences in cardiac electrophysiology and may have implications for gender specific design of anti-arrhythmic drugs and biological pacemakers.

A Production Planning and Control (PPC) system for soft drink production is developed as a distributed system to cope with the uncertain economic environment, diversified customers needs and plant disturbances. The paper describes a novel approach for design a small intelligent PPC system based on holonic concepts and using the methodology of Generalized Nets (GNs). The proposed approach is very suitable for planning and control of hybrid production systems and is applied using the software tool “GNET” with DDE connection to the MS - Office.

Subject of this article is a new cooling model based control system of a hot strip mill runout table. A method of combined global and local control is presented, using numerical and analytical models of the cooling process. A Quadratic Dynamic Matrix Control algorithm is applied to the cooling system on the ronout table of a 1700 Hot Strip Mill and the optimal tuning parameters are found.

Between tradition (Hilberts 12th Problem) and actual challenges (coding theory) we attack infinite two-dimensional Galois theory. From a number theoretic point of view we work over ℚ(x). Geometrically, one has to do with towers of Shimura surfaces and Shimura curves on them. We construct and investigate a tower of rational Picard modular surfaces with Galois groups isomorphic to the (double) octahedron group and of their (orbitally) uniformizing arithmetic groups acting on the complex 2-dimensional unit ball 𝔹.

The sinus node (SN) is the heart’s primary pacemaker and has a unique expression of pacemaking ion channels and immune cell markers. The role of microribonucleic acids (miRNAs) in control of ion channels and immune function of the sinus node is not well understood. We have recently shown that hsa-miR-486-3p downregulates the main pacemaking channel HCN4 in the SN. In addition, we recently demonstrated that immune cells are significantly more abundant in the SN compared to the right atrium. The aim of this study was to validate the previously predicted interactions between miRNAs and mRNAs of key Ca2+ ion channels (involved in peacemaking) and mRNA of TPSAB1—(a mast cells marker) using luciferase assay. We now show that miR-486 significantly downregulates Cav1.3, Cav3.1, and TPSAB1-mediated luciferase activity, while miR-938 significantly downregulates only TPSAB1-mediated luciferase activity. This makes miR-486-3p a potential therapeutic target in the treatment of SN dysfunctions.