Odd Values Research Articles

QTLs and Candidate Genes for Seed Protein Content in Two Recombinant Inbred Line Populations of Soybean.

This study aimed to discover the quantitative trait loci (QTL) associated with a high seed protein content in soybean and unravel the potential candidate genes. We developed two recombinant inbred line populations: YS and SI, by crossing Saedanbaek (high protein) with YS2035-B-91-1-B-1 (low protein) and Saedanbaek with Ilmi (low protein), respectively, and evaluated the protein content for three consecutive years. Using single-nucleotide polymorphism (SNP)-marker-based linkage maps, four QTLs were located on chromosomes 15, 18, and 20 with high logarithm of odds values (5.9-55.0), contributing 5.5-66.0% phenotypic variance. In all three experimental years, qPSD20-1 and qPSD20-2 were stable and identified in overlapping positions in the YS and SI populations, respectively. Additionally, novel QTLs were identified on chromosomes 15 and 18. Considering the allelic sequence variation between parental lines, 28 annotated genes related to soybean seed protein-including starch, lipid, and fatty acid biosynthesis-related genes-were identified within the QTL regions. These genes could potentially affect protein accumulation during seed development, as well as sucrose and oil metabolism. Overall, this study offers insights into the genetic mechanisms underlying a high soybean protein content. The identified potential candidate genes can aid marker-assisted selection for developing soybean lines with an increased protein content.

Impact of temporal variations and risk factors associated with udder inflammation in Hardhenu cattle (Bos taurus × Bos indicus).

This study aimed to explore the occurrence and risk factors associated with clinical mastitis within the Hardhenu cattle herd over a span of 14 years (2008-2021). A comprehensive analysis of 1515 lactation records was conducted to ascertain the incidence of clinical mastitis. The investigation determined an overall incidence rate of 26.80% in the studied population. A significant relationship between the year and clinical mastitis incidence was established through Chi-square analysis (p < .05). Temporal variations in clinical mastitis odds were apparent, with the highest odds (ranging from 0.91 to 1.00) observed during the initial years of 2008-2009 and 2009-2010. Logistic regression revealed that odds values for clinical mastitis incidence were highest in 2008-2009 (1.00), succeeded by 2009-2010 (0.91), 2012-2013 (0.88), 2018-2019 (0.67) and reaching the lowest in 2021-2022 (0.35). Subsequent rankings included 2010-2011 (0.39), 2014-2015 (0.43) and 2019-2020 (0.45). Parity was found to be significantly associated with clinical mastitis occurrence. When compared to Parity 3, both Parity 1 (odds ratio: 1.516, 95% confidence interval: 0.881-2.612) and Parity 2 (odds ratio: 2.626, 95% confidence interval: 1.568-4.398) exhibited higher odds values for clinical mastitis incidence. While the period of calving did not exert a significant influence on clinical mastitis incidence, a heightened occurrence was observed during the rainy season within the targeted population. These findings offer valuable insights into the patterns of incidence, temporal fluctuations, and non-genetic determinants impacting clinical mastitis within the Hardhenu cattle. The implications of this study can facilitate the development of targeted strategies and management protocols aimed at enhancing udder health and overall productivity in dairy cattle.

Quantitative Trait Locus Analysis of Hessian Fly Resistance in Soft Red Winter Wheat.

The Hessian fly (HF) is an invasive insect that has caused millions of dollars in yield losses to southeastern US wheat farms. Genetic resistance is the most sustainable solution to control HF. However, emerging biotypes are quickly overcoming resistance genes in the southeast; therefore, identifying novel sources of resistance is critical. The resistant line "UGA 111729" and susceptible variety "AGS 2038" were crossbred to generate a population of 225 recombinant inbred lines. This population was phenotyped in the growth chamber (GC) during 2019 and 2021 and in field (F) trials in Georgia during the 2021-2022 growing seasons. Visual scoring was utilized in GC studies. The percentage of infested tillers and number of pupae/larvae per tiller, and infested tiller per sample were measured in studies from 2021 to 2022. Averaging across all traits, a major QTL on chromosome 3D explained 42.27% (GC) and 10.43% (F) phenotypic variance within 9.86 centimorgans (cM). SNP marker IWB65911 was associated with the quantitative trait locus (QTL) peak with logarithm of odds (LOD) values of 14.98 (F) and 62.22 (GC). IWB65911 colocalized with resistance gene H32. KASP marker validation verified that UGA 111729 and KS89WGRC06 express H32. IWB65911 may be used for marker-assisted selection.

Mercury Sources and Fate in a Large Brackish Ecosystem (the Baltic Sea) Depicted by Stable Isotopes.

Identifying Hg sources to aquatic ecosystems and processes controlling the levels of monomethylmercury (MMHg) is critical for developing efficient policies of Hg emissions reduction. Here we measured Hg concentrations and stable isotopes in sediment, seston, and fishes from the various basins of the Baltic Sea, a large brackish ecosystem presenting extensive gradients in salinity, redox conditions, dissolved organic matter (DOM) composition, and biological activities. We found that Hg mass dependent fractionation (Hg-MDF) values in sediments mostly reflect a mixing between light terrestrial Hg and heavier industrial sources, whereas odd Hg isotope mass independent fractionation (odd Hg-MIF) reveals atmospheric inputs. Seston presents intermediate Hg-MDF and odd Hg-MIF values falling between sediments and fish, but in northern basins, high even Hg-MIF values suggest the preferential accumulation of wet-deposited Hg. Odd Hg-MIF values in fish indicate an overall low extent of MMHg photodegradation due to limited sunlight exposure and penetration but also reveal large spatial differences. The photodegradation extent is lowest in the central basin with recurrent algal blooms due to their shading effect and is highest in the northern, least saline basin with high concentrations of terrestrial DOM. As increased loads of terrestrial DOM are expected in many coastal areas due to global changes, its impact on MMHg photodegradation needs to be better understood and accounted for when predicting future MMHg concentrations in aquatic ecosystems.

Hubungan Ketepatan Kode Diagnosis Terhadap Status Klaim JKN Rawat Inap di Rumah Sakit Pelabuhan Jakarta

The accuracy of determining the diagnosis code is necessary for the benefit of patient health information in carrying out health services. The accuracy of the diagnosis code is also required for the benefit of claiming National Health Insurance (JKN). The research aims to determine the correlation between the accuracy of the diagnosis code and the status of inpatient National Health Insurance (JKN) claims. The research method was an inferential analysis with a cross-sectional research design using the chi-square statistical test. The samples of the research were 125 medical records. Samples were taken by way of proportional stratified random sampling. Based on the research results, the accuracy of determining the diagnosis code was 114 (91,2%) while the inaccuracy of determining the diagnosis code was 11 (8,8%). JKN claims received were 104 (83,2%) while JKN claims that were postponed were 21 (16,8%). The results of the chi-square statistical test obtained odd ratio value of 20,7, meaning that the correct diagnosis codes has 20,7 times chance of JKN claims approval than the incorrect diagnosis codes. The significance value obtained of 0.000. The p-value shows &lt;0.05, so Ho is rejected and Ha is accepted or there is a correlation between the accuracy of the diagnosis code and the status of inpatient JKN claims at the Pelabuhan Jakarta Hospital. This research concludes that there is a correlation between the accuracy of the diagnosis code and the status of inpatient JKN claims.

Ramanujan’s formula for odd zeta values: a proof by Mittag-Leffler expansion and applications

Using Mittag-Leffler expansion a novel proof of Ramanujan’s famous formula for zeta (2m-1) is presented. Here, the formula can be derived by Taylor series of a generating function and its Mittag-Leffler expansion. Furthermore, generalized formulas for the fast-converging series of Plouffe are offered. But Ramanujan’s equation not only produces series for odd zeta values, surprisingly it is shown that in the limit to its singularity it provides the identities for even zeta values, namely Euler’s classical formula. Finally, a new triangle identity of Ramanujan’s formula is presented, hinting that properties and symmetries of the equation are far from all uncovered. For this work, a new representation of the equations is introduced, that significantly simplifies analyses and applications.

Structural distinction of zigzag-edge coronoids analyzed by spectroscopies

Unlike armchair-edge coronoids, the band gap of zigzag-edge coronoids (ZCs) can be adjusted via the molecular and cavity sizes. Herein, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy are used to identify 12 structures of ZCs with different molecular and cavity sizes. Evidently, the C1s peak positions of the ZCs depend on the number of carbons (NC) between the inner and outer edges: they shift to a lower and higher binding energy if the ZCs have an even and odd value of NC, respectively, compared with that of structures without a cavity because of the change in band gap. The C1s peak positions of ZCs with NC = 2 and NC = 3–6 differ by more than 0.4 eV. Raman spectroscopic analysis reveals that the detected characteristic modes depend on NC. For structures with NC = 2, C−H vibration and C−C stretching vibration mode bands are observed, whereas for structures with NC = 3–6, C−H vibration and breathing mode bands are observed. In particular, the band originating from the C−H vibration on the inner edge appear in structures with NC = 3–6 and a pore size larger than 8.26 Å. As the molecular size increases, the intensities of the characteristic bands change and the breathing mode band shift to a higher wavenumber. These results indicate that the molecular and cavity sizes of the ZCs can be distinguished using XPS and Raman spectroscopy.

Hurwitz zeta functions and Ramanujan's identity for odd zeta values

Inspired by a famous formula of Ramanujan for odd zeta values, we prove an analogous formula involving the Hurwitz zeta function. We introduce a new integral kernel related to the Hurwitz zeta function, generalizing that associated to Ramanujan's identity. We also derive several infinite families of identities analogous to Ramanujan's formula.

The Relationship Between Physical Activity and Sleep Duration on The Incidence of Obesity in Children under Five in Central Jakarta and The Review of Islamic Perspective

Introduction: The excessive buildup of fat, known as obesity, can negatively affect health. In 2020, there will be 38.9 million overweight children under the age of five worldwide. 7.8% of toddlers in DKI Jakarta are fat, compared to 7.04% in central Jakarta. A variety of factors cause obesity. The two most important factors are insufficient sleep time and physical exercise. Methodology: This type of research is quantitative with a cross-sectional design. The study population was toddlers in Sawah Besar District, Central Jakarta, a total of 70 people. Results: The results showed that 33 people (47.1%) were ordinary, four people (5.7%) were at risk of being overweight, three people (4.3%) were fat, and 30 people (42.9%) were obese. Moderate physical activity was found in 15 people (50%) normal and 15 people (50%) obese. At the same time, physical activity is less, with as many as 18 people (45%) ordinary and 22 people (55%) obese. Found adequate sleep duration in 21 people (63.648%) were ordinary, and 12 (36.36%) were obese. At the same time, the rest period is seen in as many as 12 people (32.43%) normal and 25 people (67.57%) obese. P=0.810 and p=0.016 show differences in physical activity and sleep duration in obese toddlers. Conclusion: In toddlers in the Sawah Besar District of Central Jakarta, there is a meaningful association between sleep duration and the incidence of obesity (p=0.016) and no relationship between physical activity and the incidence of obesity (p=0.810) with an Odd Ratio value of 1.222.

The Relationship of Sedentary Behavior and Sleep Duration to The Incidence of Obesity in Children under Five in Central Jakarta and The Review of Islamic Perspective

Introduction: Children under five should have their nutritional status checked regularly due to their susceptibility to diseases and nutritional problems. Inappropriate or excessive accumulation of fat, called obesity, can jeopardize their health. Assessment of nutritional status in obese toddlers can use anthropometric standards that are converted into Z-score values based on IMT/U with the category of obesity if the Z-score value is &gt; +3 SD. Sedentary behaviour is when a person spends sitting or lying down with low energy expenditure outside sleep. Children and adolescents with high sedentary behaviour are prone to an increase in adipocytes that cause obesity. Children aged 3-5 years with poor sleep duration (&lt;10 hours/day) are at greater risk of obesity. Methods: This type of research is quantitative with a cross-sectional design. The sample of this study was 70 children aged 2-5 years in Sawah Besar District, who were included in the inclusion criteria. Results: Out of 70 toddlers in Central Jakarta, 37 people (52.9%) were obese, and 33 (47.1%) were ordinary. Based on the results of statistical tests using the Chi-Square test, the p-value is &lt;0.05, which can be concluded that there is a relationship between sedentary behaviour and obesity and a relationship between sleep duration and obesity. Conclusion: The research results show a significant relationship (p 0.03) between sedentary behaviour and obesity, with an Odd Ratio value of 3.137. There is also a meaningful relationship (p 0.016) between sleep duration and obesity, with an Odd Ratio value of 3.646 in Sawah Besar District, Central Jakarta toddlers.

Analisis Kemampuan Siswa SMP dalam Menerjemahkan Soal Cerita SPLDV dan Penyelesaiannya

This study aims to determine the ability of junior high school students in translating SPLDV word problems into mathematical models and their solutions. Especially in the matter of two-variable linear equation systems (SPLDV).&#x0D; This type of research is qualitative. The approach used is the phenomenological approach. Data collection using test techniques, interviews, field notes, and documentation. The research subjects took 2 students with high category classification from class VIII B of SMP Negeri 2 Puring which originated from the determination of high, medium and low group boundaries. The group limit is high if the Odd PAS value is &gt; (x ̅ + SD), the group limit is medium if (x ̅ - SD) &lt; Odd PAS value &lt; (x ̅ + SD), while the group limit is low if the Odd PAS value &lt; (x ̅ + SD). Data analysis techniques include data reduction, data presentation, and conclusions. Checking the validity of the data uses credibility and confirmability tests.&#x0D; The results of this study indicate that the subject has a high ability to translate because he is able to understand the problem (write down what is known and asked), is able to solve problems (make examples and mathematical models), is able to take steps to solve problems. But did not evaluate or check again. Students who have high translation skills experience a few mistakes, namely not carrying out the evaluation step or checking again.

Parity of the coefficients of certain eta-quotients, II: The case of even-regular partitions

We continue our study of the density of the odd values of eta-quotients, here focusing on the m-regular partition functions bm for m even. Based on extensive computational evidence, we propose an elegant conjecture which, in particular, completely classifies such densities: Let m=2jm0 with m0 odd. If 2j<m0, then the odd density of bm is 1/2; moreover, such density is equal to 1/2 on every (nonconstant) subprogression An+B. If 2j>m0, then bm, which is already known to have density zero, is identically even on infinitely many non-nested subprogressions. This and all other conjectures of this paper are consistent with our “master conjecture” on eta-quotients presented in the previous work.In general, our results on bm for m even determine behaviors considerably different from the case of m odd. Also interesting, it frequently happens that on subprogressions An+B, bm matches the parity of the multipartition functions pt, for certain values of t. We make a suitable use of Ramanujan-Kolberg identities to deduce a large class of such results; as an example, b28(49n+12)≡p3(7n+2)(mod2). Additional consequences are several “almost always congruences” for various bm, as well as new parity results specifically for b11.We wrap up our work with a much simpler proof of the main result of a recent paper by Cherubini-Mercuri, which fully characterized the parity of b8.

Hubungan Perilaku dengan Kejadian Diabetes Melitus Tipe 2 di Puskesmas Kota Ende Tahun 2021

Diabetes mellitus is a serious and chronic (prolonged) disease that causes metabolic intrusion and obstruction, indicated by high blood sugar beyond the normal level. Unhealthy lifestyles, such as smoking, drinking alcohol, bad dietary habit and obesity, lacking of physical activities, and stress, are some of the main contributors or causes of diabetes mellitus. The purpose of this research is to find the direct connection and relation between the behaviour or lifestyle and the case of Diabetes Mellitus Type 2 at Ende City Health Center. The design of this research is a survey analytic research using a case-control approach. The total sample in this research is 86 respondents, with a 1:1 (one-to-one) comparison. The sampling technique used in this study is simple random sampling. The data is taken by doing a guided interview with a questionnaire for test statistic chi-square and odd ratio value. The result of this research shows that the variable of dietary habit (p-value = 0,017 &lt; 0,05 and OR = 3,168 (1,309 – 7,665 and 95% CI), physical activities (p-value = 0,028 &lt; 0,05 and OR = 2,971 (1,212 – 7,279 and 95% CI), consumption of alcohol (p-value = 0,023 &lt; 0,05 and OR = 3,285 (1,273 – 8,478 and 95% CI) directly connected with the case of Diabetes Mellitus Type 2. The variable of knowledge (p-value = 0,829 &gt; 0,05 and OR = 1,206 (0,516 – 2,816 and 95% CI) does not have any connection with the case of Diabetes Mellitus Type 2. Suggestion for the healthcare workers in the Ende City Health Center to always improve and maintain good service of the health care and for the people to have regular check-ups and to develop healthy lifestyle such as having proper dietary habits, doing physical activities and controlling the consumption of alcohol to control the level of blood sugar.

Impact of anxiety and depression across childhood and adolescence on adverse outcomes in young adulthood: a UK birth cohort study.

Little is still known about the long-term impact of childhood and adolescent persistent depression and anxiety in adulthood. To investigate the impact of persistent anxiety, depression, and comorbid anxiety and depression across childhood and adolescence on the development of multiple adverse outcomes in young adulthood. This study used data from 8122 participants in the Avon Longitudinal Study of Parents and Children cohort. The Development and Well-Being Assessment (DAWBA) examined child anxiety and depression symptomatology. The DAWBA generalised anxiety and mood subscales at 8, 10 and 13 years were selected, and a measure of comorbid anxiety and depression symptoms was created at each time point. Further, several mental and physical health, substance misuse and education/employment problems were assessed at 24 years. Latent class growth analyses were used to detect trajectories of anxiety, depression and comorbid anxiety and depression; and logistic regression to examine how persistent anxiety, depression or both were associated with adverse outcomes at 24 years. All three classes with persistent anxiety, depression or both were significantly associated with presenting with any mental health problems and any education/employment problem. Persistent high levels of depression and high levels of comorbid anxiety and depression, but not persistent high anxiety, were significantly associated with any physical health problem. High levels of comorbid anxiety and depression was the only DAWBA domain significantly associated with substance misuse; and overall, this was the domain that exerted the greatest negative impact, as it presented the highest odd ratio values. Children and adolescents with comorbid anxiety and depression are at the highest risk for having more adverse outcomes at 24 years.

Linking Climate Change Awareness, Climate Change Perceptions and Subsequent Adaptation Options among Farmers

Several studies have reported farmers’ perceptions of climate change, but there is inadequate knowledge available on the farm households’ climate change awareness (CCA) in Pakistan. This study was undertaken to assess farmers’ CCA. For this purpose, the study collected the data from southern and central Punjab, Pakistan, through a purposively multistage random sampling technique. Binary logit and odds ratio were used to analyse the data. The analysis of the study shows that the majority of respondents were aware of climate change but had differing perceptions of climate change. This research showed that 70.8% of farmers are aware of climate change and reported their awareness level on winter and summer rainfall and temperature, the growing season length (GSL) of crops, the sea level rise, and the causes of climate changes and conceptual understanding of it while persistently denying climate change. However, many farmers did not perceive decreasing winter (48%) and summer (31.2%) precipitation, the majority of the farmers could not perceive in the GSL of summer (63.2%) and winter (64.4%) crops, while few did not notice increased winter (36.4%) and summer (33.6%) temperature, respectively. Financial and non-financial factors such as education (1.16), experience (1.07), distance to markets (1.07), non-agricultural income (2.83), access to agricultural credit (0.29) and marketing of produce (6.10), access to extension services (3.87) and the number of adaptation strategies (1.30) were pointedly related to farm households’ CCA. These odds values in the parenthesis show that the likelihood of CCA increases/decreases as these determinants increase. Moreover, the results of the study show that CCA is a significant predictor of adaptation to climate change. Main adaptation strategies opted for by farmers include changing crop variety and type, changing planting dates, tree plantation, increasing/changing fertilizer, soil and water conservation, off-farm income and diversification. Further, the study finds that some farmers did not perceive climate change as it takes time to be visible, but they are aware of climate change. Therefore, there is a need to reshape the households’ perception of climate change and enhance farmers’ CCA through existing extension services.

PENGARUH FASILITAS BELAJAR, MOTIVASI BELAJAR, DAN DISIPLIN BELAJAR TERHADAP HASIL BELAJAR MATA PELAJARAN HUMAS KELAS XI OTKP DI SMKN JAKARTA BARAT

The purpose of this study was to determine the influence of learning facilities, learning motivation, and learning discipline on the learning outcomes of class XI OTKP public relations subjects of SMK Negeri in West Jakarta. The population in this study is SMKN which has an OTKP major in West Jakarta. The sample in this study was 133 students, this number was obtained from calculations based on the tables of Isaac and Michael. The sampling technique uses the propotional random sampling method. The data collection in this study is secondary data using a questionnaire based on a likert scale for independent variables while for dependent variables using secondary data obtained from the school that is used as the research site in the form of the results of the odd midterm assessment value 2021/2022. The test results using SMARTPLS show: (1) there is an influence between learning facilities on learning outcomes, (2) there is an influence between learning motivation on learning outcomes, (3) there is an influence between learning disciplines on learning outcomes.

Nuclear Energy Levels in 44Ca using FPD6pn Interaction

Nuclear energy levels; total angular moment, even-even parity, and even odd parities for nucleons that were present outside closed core for the isobars 44Ca nuclei, which occupied low levels fp-LS shell (1f7/2,1f5/2, 2p3/2,2p1/2), within shell model calculations had been studied. The interaction has been used to calculate the nuclear energy levels which are fpd6pnwith fp shell model space. The results are compared with each other and with available experimental data, its agreement with some results is clear. All inscriptions are given in diagrammatic notation., the wave vectors and analysis are modeled in the so-called diagrammatic notation. The potential of the oscillator is utilized to construct a single particle vector, considered as a core. The OXFORD BEUNES AIRES SHELL MODEL CODE (OXBASH) is utilized to accomplish the results for all tested nuclei, the results as illustrated in figure (1) revealing that the levels have somehow consisted especially below 4 MeV, and the order are arranged similarly to the experimental scheme. All the states inherent above 4MeV are shifted especially for the odd values of total spin (J), so the model and interaction need to be modified.

Association of Anemia with Parathyroid Hormone Levels and Other Factors in Patients with End-Stage Renal Disease Undergoing Hemodialysis: A Cross-Sectional, Real-World Data Study in Pakistan.

End-stage renal disease (ESRD) patients are mostly managed with maintenance hemodialysis (MHD). ESRD patients on MHD also present with many complications, such as anemia, hyperparathyroidism, and hepatitis prevalence. This study depicts the real-world scenario of anemia among MHD and end-stage renal disease patients in the Pakistani population. A retrospective, multicentric, and real-world data analytical study was conducted at 4 dialysis centers in Pakistan. The study had a sample size of n = 342 patients on maintenance hemodialysis. The data were gathered from the medical records of patients. Data analysis was performed using STATA Version 16. Statistical significance was gauged at a 0.05 level of significance. According to our results, the mean age of the patients was 45 (±15) years. Most of the patients were male (n = 234, 68.4%), whereas 58.1% of the patients were maintained on twice-weekly hemodialysis. The most commonly reported comorbidities were hypertension and diabetes mellitus. The frequency of dialysis (P < 0.01) and comorbidities (P = 0.009) had a significant association with anemia in MHD patients. The majority of the patients had hyperparathyroidism (52%) with anemia. Upon performing binary logistic regression, multivariate analysis displayed a similar odds value for having anemia in patients with every additional month in the duration of hemodialysis (OR 1.01, P = 0.001), the odds of anemic patients having a positive antihepatitis-C antibody (OR 2.22, P = 0.013), and the odds of having anemia in patients in the age category below 45 years (OR 1.93, P = 0.013). In conclusion, the study results depict that every additional month in the duration of hemodialysis, age (<45 years), and positive anti-HCV antibody status, these variables were more likely to have anemia in our study MHD patients. While in our final multivariate model, no statistically significant association was observed between hyperparathyroidism and anemia.

Sets of Nonbinary Sequences with a Low Level of Mutual Correlation for Systems of Digital Information Transmission

The sets of nonbinary pseudorandom sequences (NPSs) for periods N = p^S– 1 20 000 (p = 3, 5,7, and 11) generated in finite fields GF(pS) whose power is V = N + 1 and the maximum of the module of peaks of the periodic autocorrelation function (PACF) and periodic cross-correlation function (PCCF) satisfy the bounds obtained by Sidel’nikov. In addition to the minimal polynomials of elements α and α^2 , where α is a primitive element of field GF(p^S), the minimal polynomials of elements α and α^(i_d)(i_d is the decimation index) are determined on the basis of which the new sets of NPSs can be formed with the equivalent correlation properties. Sets of indices i_d 2 are determined for various combinations of parameters p and S. The cases of even and odd values of parameter S are considered, for which the values of the PACF and PCCF with the maximum module are obtained and the number and values of different levels of correlation functions are determined.

Autocorrelation-based algorythm to detect alternans in calcium buffered ventricular myocytes.

Both action potential (AP) alternans (AP-ALT) and intracellular calcium transient (CaT) alternans (CaT-ALT) are arrhythmogenic. Since AP and CaT are bidirectionally coupled, either signal's dynamic response theoretically affects alternans formation in its counterpart. It was shown that CaT-ALT do not require AP-ALT, but whether AP-ALT require CaT-ALT is not well known. Because in isolated myocytes AP-ALT readily change amplitude and persistence, we developed an autocorrelation-based algorithm to objectively detect AP-ALT, and used it to assess how removing CaT-ALT impacts AP-ALT formation. Tyrode perfused (37 oC) isolated rabbit ventricle myocytes were paced at progressively shorter pacing cycles lengths (BCL) from 500 ms to the shortest BCL>179 ms eliciting AP-ALT (>14 consecutive 2:2 activations), i.e. the alternans threshold (ALT-TH). We determined the AP duration (APD) of the last 40 APs at each BCL. The average cross-correlation between the original 40-APD sequence and its mathematically shifted equivalent (shifts equaled odd values 1-through-7) yielded the autocorrelation index (ACI). CaT was abolished using 20 mM BAPTA. 65% control myocytes were alternans positive. ACI ranged from 0 to −1 and correlated negatively with the duration of consecutive long-short APD sequences (alternans)(R=-0.9062, p<0.0001), thus effectively reporting the absence/presence of alternans. Versus controls, BAPTA increased the AP-ALT incidence and ALT-TH (65 vs 91%; 226±36 vs 273±56 ms, p<0.03), but did not change the ACI of alternans positive cells (0.07±0.09 vs 0.13±0.11 at 500 ms BCL; −0.66±0.17 vs −0.60±0.22 at ALT-TH; 2-way-ANOVA p>0.05 factor-group and p<0.0001 factor-BCL). Concomitantly, at ALT-TH BAPTA prolonged APD (225±52 vs 180±34 ms in control, p<0.02), but the diastolic interval remained unaltered. Our autocorrelation-based algorithm efficiently detects alternans. AP-ALT thrive in the absence of CaT and are more sensitive to activation rate changes. Therapies aiming to reduce CaT or its dynamic response should consider this.